Error message 0x0

Question

Error message 0x0

Amy Gallagher 10

Won't let me sign into 365, get error message 0x0

Have already restarted my Mac

Locked Question. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.

Desmond Kipenge 5 Reputation points

2026-07-14T09:30:55.27+00:00
Hello,

Since this morning I have been experiencing an issue with Microsoft Outlook on one specific iMac.

Environment:

macOS Ventura 13.7.8

Microsoft Outlook for Mac

Problem: When I launch Outlook, I receive the following error message:

"Unknown Error. An unknown error has occurred. Error code: 0x0"

I have attached a screenshot of the error.

Additional information:

The issue occurs only on this iMac.

All other Macs in the office are working correctly.

All other Microsoft applications on the affected iMac are functioning normally.

The problem affects only Outlook.

I followed all the troubleshooting steps described in the following Microsoft page, but the issue persists: https://learn.microsoft.com/en-sg/answers/questions/5945823/error-message-0x0

At this point, I have already spent more than three hours trying to resolve the issue without success.

Could you please advise on any additional troubleshooting steps or provide a solution?

Thank you for your assistance.Hello,

Since this morning I have been experiencing an issue with Microsoft Outlook on one specific iMac.

Environment:

macOS Ventura 13.7.8

Microsoft Outlook for Mac

Problem: When I launch Outlook, I receive the following error message:

"Unknown Error. An unknown error has occurred. Error code: 0x0"

I have attached a screenshot of the error.

Additional information:

The issue occurs only on this iMac.

All other Macs in the office are working correctly.

All other Microsoft applications on the affected iMac are functioning normally.

The problem affects only Outlook.

I followed all the troubleshooting steps described in the following Microsoft page, but the issue persists: https://learn.microsoft.com/en-sg/answers/questions/5945823/error-message-0x0

At this point, I have already spent more than three hours trying to resolve the issue without success.

Could you please advise on any additional troubleshooting steps or provide a solution?

Thank you for your assistance.
Norah-L 8,155 Reputation points Microsoft External Staff Moderator

2026-07-15T05:02:52.3966667+00:00

Hi Desmond Kipenge,

I'm sorry you're facing this issue as well. I understand that Outlook shows the “Unknown Error” message with error code 0x0 when launched on one iMac running macOS Ventura 13.7.8, while the other Office apps and Macs work normally.

First, please select Apple menu > About This Mac and check the iMac model and year. If the iMac supports macOS Sonoma, back up the Mac, then update to macOS 14 or later from System Settings > General > Software Update. Afterward, open an Office app and select Help > Check for Updates to install the latest Office updates.

If the iMac cannot be upgraded beyond macOS Ventura, try reinstalling Outlook using a standalone installer from Release history for Office for Mac (from the Office 16.101 release line), which is the final Office for Mac version officially documented as compatible with Ventura. Please note that this is a workaround, as Ventura no longer receives newer Office feature or security updates.

Let me know how it goes!
sheri s 0 Reputation points

2026-07-17T03:46:52.0966667+00:00

Those are only updaters there is no outlook for Ventura stand alone.
sheri s 0 Reputation points

2026-07-17T03:47:50.3933333+00:00

I am having same issue and am running Ventura. If i could find a stand alone outlook for Ventura that would be great. I searched for 5 hours.
Norah-L 8,155 Reputation points Microsoft External Staff Moderator

2026-07-17T04:15:09.8833333+00:00

sheri s, thank you for the clarification and your additional information. It seems that only standalone update releases are available, rather than a standalone Outlook installation package.

In this situation, another option is to completely reinstall the Office suite using an installer from the same 16.101 release line in Release history for Office for Mac.

Before trying that, you may also want to review these Microsoft articles:

Unknown Error 0x0 or License not found error in Microsoft 365 or Office running on macOS

Update Microsoft 365 or Office on your macOS or iOS device
sheri s 0 Reputation points

2026-07-17T15:16:06.69+00:00

I never used outlook and as I purchased through the App Store and my other apps are working word excel and PowerPoint i am not goign to touch anythign. I am so traumatized by all this. And am without words. I need the programs tp run my business and what is goign on is a crime. I have 2 subscriptions. Have no idea now which one i can cancel get no information from anyone . Apple made me repurchase the subscription in order to download form the App Store despite my already having an active subsciption. When i went to ign in wiht THE SAME USER NAME AND PASSWORD I HAVE WITH MICROSFT IT SAID BUY AND I WAS STUCK!!!ANY INFORMATION ABOUT WHICH I CAN CANCEL WOULD BE SO HELPFUL. UNFORTUANTELY HAVE 2 APPLE IDS AND EACH HAS A SUBSCRITOION YET ONLY ONE MICROSFOT ACCOUNT.
Norah-L 8,155 Reputation points Microsoft External Staff Moderator

2026-07-19T08:23:24.61+00:00
sheri s, I’m really sorry this has become so stressful, especially when you rely on Word, Excel, and PowerPoint for your business. Since those apps are working, I agree that you should not reinstall or remove anything right now.

Because both subscriptions were purchased through the App Store, billing and refunds must be handled by Apple rather than Microsoft.

Before cancelling anything:

Sign in to each Apple ID and open App Store > Account Settings > Subscriptions.

Check the Microsoft 365 plan, purchase date, renewal date, and price under each Apple ID. Apple also recommends checking the “receipt from Apple” emails to identify which Apple ID made each purchase.

If the original subscription still shows as Active, cancel the newer duplicate subscription under the other Apple ID and submit a refund request to Apple, explaining that it was purchased only because the existing subscription was not recognized.

If the details remain unclear, contact Apple Billing Support and provide both order receipts so they can identify the duplicate and advise which purchase can be refunded safely.
sheri s 0 Reputation points

2026-07-19T14:39:40.4+00:00

Norah. Thank you for your advise but i have done all of that. I called apple. They say they can not advise which to cancel/. Signing into both the differnt apple ids they both are there. I have under 2 apple ids. The microsoft page shows only the original. The one not recognized. But i am wondering if this is not because the one i bought Tuesday is still in free trial mode. Once Microsoft receives the money in august it will show. I only have one Microsoft account. Same user name and password i have used for years. The chat in Microsoft store advised to cancel the older one. The one not recognized. Why would you say to cancel the new annual one rather than the old monthly . That makes no sense to me. The new apps i had to download only started working after i hit buy and purchased the annual. I do. Not understand your advice. Apple does nto provide that answer. I tried adn called.
Norah-L 8,155 Reputation points Microsoft External Staff Moderator

2026-07-20T00:32:25.42+00:00
Hi sheri s

Why would you say to cancel the new annual one rather than the old monthly

I’m sorry for the confusion. I initially thought the new annual subscription was an accidental duplicate while the monthly one was still working, so I suggested canceling the newer purchase to prevent overlapping charges. Now that you have clarified the situation, I understand why canceling it would not make sense.

But i am wondering if this is not because the one i bought Tuesday is still in free trial mode. Once Microsoft receives the money in august it will show.

That is one possibility. The App Store purchase includes a one-month free trial, so if you bought it on Tuesday and Apple will not charge you until August, the annual subscription may currently be in its trial period.

However, another possibility is that the App Store purchase has not been properly linked to your Microsoft account. I've found a similar Microsoft Q&A thread, My paid subscription from Apple is not registering with Microsoft, where the OP purchased Microsoft 365 through the Apple App Store but the purchase could not be associated with their Microsoft account. Another user also reported that their Apple trial had started but was not registering with Microsoft.

Please note that if your Microsoft 365 subscription was purchased through a third-party provider, that provider is responsible for managing cancellations, renewals, and payment methods. However, you may still contact Microsoft Support to see whether they can offer any advice. As this is a user‑to‑user community forum, we can only share suggestions based on our findings and personal experiences, we cannot access or verify your account, purchase, or subscription details.

Here's how to reach out to the Support Team (live chat):

Go to: https://support.microsoft.com/home/contact

In the search box, enter a short description of your issue.

Hit "Get Help"

Scroll down and select Sign in to contact support for further assistance (please sign in using a personal Microsoft account). Then follow the on-screen prompts to reach Support Team.

Tip: Support chat availability may vary by country/region, product, and support hours. If you can't get in touch with a chat agent right away, trying again later or at a different time may help.

Thank you so much for your patience!

Best regards.
sheri s 0 Reputation points

2026-07-20T00:50:03.0566667+00:00

Norah,

I am afraid your attempt at helping me is in fact not really helping me. I am not even sure if you work for Microsoft.

it was not until I purchased again from the APP STORE that the apps worked and i was able to use them. i also contacted the microsoft store, a chat, with someone named Matt who was able to see both accounts with the 2 different ids. I am not sure you really know what you are talking about. IF so, then please speak with a Microsoft supervisor to rectify this situation. you are making it even more confusing for me. i already know how to reach out to the support team. what a joke. not one gets back to you and i had 3 open cases. i am at my wits end. I personally have tried everything. to no avail. you are also adding comments from 2025 above.
Haytham-C 4,300 Reputation points Microsoft External Staff Moderator

2026-07-20T01:38:51.6033333+00:00

Hello sheri s
I'm so sorry to hear that the issue still remains unresolve. As Norah inform earlier, we as a Microsoft Community moderator, can only help by sharing relevant Microsoft documentation and troubleshooting resources available to the public and related to your issue. Since we do not have access to internal diagnostic tools or product backend side, I can only recommend reaching out to Microsoft Support live chat again and once connected, please inform the supporting agent with all the step you've tried and your previous case number, and you can also request escalation on your case for further investigation if the issue still persists. I understand how frustrating this situation can be but with limited authorization, we can only guide you to the correct supporting channel.
Thank you for your understanding.
sheri s 0 Reputation points

2026-07-20T01:54:19.4933333+00:00

thank you. i do not know how much more time i have to waste on this, as i have told upteen people i will wait until the free trial is over to see if that shows up in my microsoft account as redeemed. my plan is to cancel the old subscription. that seems to be the majority consensus of people reading these forums although i have no faith in anyone. i will probably contact a lawyer and hope to start a class action for the poor support and aggravation i have received. it is corrupt what occurred to me and then no one responds with accurate information. for a company so large this should be the least respect someone should receive. ie which subscription they can safely cancel because of their errors and bugs. i am sure someone at microsoft has that answer. the chat does not work. i have tried 22 times. it only generates a case number. the calls i received back were from 2 phillipino people that hardly spoke English , did not have the answer, and then both hung up on me. Have another idea for me?
Ian-T 7,830 Reputation points Microsoft External Staff Moderator

2026-07-21T10:01:26.8033333+00:00

Hi

I completely understand how frustrating and disappointing this experience has been. I’m truly sorry, but as a community moderator, I have no further options available and cannot access or make changes to your account or subscriptions. Thank you for your patience and understanding
Alison A 5,210 Reputation points Microsoft External Staff Admin

2026-07-21T19:30:47.1066667+00:00

Hello @Desmond Kipenge and @sheri s ,

If you continue to experience any issues, please start a new thread so the community can provide assistance tailored to your situation. Out of respect for the user who originally asked this question, and in keeping with our Community Guidelines, we'll now lock this thread.

2 answers

Norah-L 8,155 Reputation points Microsoft External Staff Moderator

2026-07-15T05:02:52.3966667+00:00

Hi Desmond Kipenge,

I'm sorry you're facing this issue as well. I understand that Outlook shows the “Unknown Error” message with error code 0x0 when launched on one iMac running macOS Ventura 13.7.8, while the other Office apps and Macs work normally.

First, please select Apple menu > About This Mac and check the iMac model and year. If the iMac supports macOS Sonoma, back up the Mac, then update to macOS 14 or later from System Settings > General > Software Update. Afterward, open an Office app and select Help > Check for Updates to install the latest Office updates.

If the iMac cannot be upgraded beyond macOS Ventura, try reinstalling Outlook using a standalone installer from Release history for Office for Mac (from the Office 16.101 release line), which is the final Office for Mac version officially documented as compatible with Ventura. Please note that this is a workaround, as Ventura no longer receives newer Office feature or security updates.

Let me know how it goes!
sheri s 0 Reputation points

2026-07-17T03:46:52.0966667+00:00

Those are only updaters there is no outlook for Ventura stand alone.
sheri s 0 Reputation points

2026-07-17T03:47:50.3933333+00:00

I am having same issue and am running Ventura. If i could find a stand alone outlook for Ventura that would be great. I searched for 5 hours.
Norah-L 8,155 Reputation points Microsoft External Staff Moderator

2026-07-17T04:15:09.8833333+00:00

sheri s, thank you for the clarification and your additional information. It seems that only standalone update releases are available, rather than a standalone Outlook installation package.

In this situation, another option is to completely reinstall the Office suite using an installer from the same 16.101 release line in Release history for Office for Mac.

Before trying that, you may also want to review these Microsoft articles:

Unknown Error 0x0 or License not found error in Microsoft 365 or Office running on macOS

Update Microsoft 365 or Office on your macOS or iOS device
sheri s 0 Reputation points

2026-07-17T15:16:06.69+00:00

I never used outlook and as I purchased through the App Store and my other apps are working word excel and PowerPoint i am not goign to touch anythign. I am so traumatized by all this. And am without words. I need the programs tp run my business and what is goign on is a crime. I have 2 subscriptions. Have no idea now which one i can cancel get no information from anyone . Apple made me repurchase the subscription in order to download form the App Store despite my already having an active subsciption. When i went to ign in wiht THE SAME USER NAME AND PASSWORD I HAVE WITH MICROSFT IT SAID BUY AND I WAS STUCK!!!ANY INFORMATION ABOUT WHICH I CAN CANCEL WOULD BE SO HELPFUL. UNFORTUANTELY HAVE 2 APPLE IDS AND EACH HAS A SUBSCRITOION YET ONLY ONE MICROSFOT ACCOUNT.
Norah-L 8,155 Reputation points Microsoft External Staff Moderator

2026-07-19T08:23:24.61+00:00

sheri s, I’m really sorry this has become so stressful, especially when you rely on Word, Excel, and PowerPoint for your business. Since those apps are working, I agree that you should not reinstall or remove anything right now.

Because both subscriptions were purchased through the App Store, billing and refunds must be handled by Apple rather than Microsoft.

Before cancelling anything:

Sign in to each Apple ID and open App Store > Account Settings > Subscriptions.

Check the Microsoft 365 plan, purchase date, renewal date, and price under each Apple ID. Apple also recommends checking the “receipt from Apple” emails to identify which Apple ID made each purchase.

If the original subscription still shows as Active, cancel the newer duplicate subscription under the other Apple ID and submit a refund request to Apple, explaining that it was purchased only because the existing subscription was not recognized.

If the details remain unclear, contact Apple Billing Support and provide both order receipts so they can identify the duplicate and advise which purchase can be refunded safely.
sheri s 0 Reputation points

2026-07-19T14:39:40.4+00:00

Norah. Thank you for your advise but i have done all of that. I called apple. They say they can not advise which to cancel/. Signing into both the differnt apple ids they both are there. I have under 2 apple ids. The microsoft page shows only the original. The one not recognized. But i am wondering if this is not because the one i bought Tuesday is still in free trial mode. Once Microsoft receives the money in august it will show. I only have one Microsoft account. Same user name and password i have used for years. The chat in Microsoft store advised to cancel the older one. The one not recognized. Why would you say to cancel the new annual one rather than the old monthly . That makes no sense to me. The new apps i had to download only started working after i hit buy and purchased the annual. I do. Not understand your advice. Apple does nto provide that answer. I tried adn called.
sheri s 0 Reputation points

2026-07-20T00:50:03.0566667+00:00

Norah,

I am afraid your attempt at helping me is in fact not really helping me. I am not even sure if you work for Microsoft.

it was not until I purchased again from the APP STORE that the apps worked and i was able to use them. i also contacted the microsoft store, a chat, with someone named Matt who was able to see both accounts with the 2 different ids. I am not sure you really know what you are talking about. IF so, then please speak with a Microsoft supervisor to rectify this situation. you are making it even more confusing for me. i already know how to reach out to the support team. what a joke. not one gets back to you and i had 3 open cases. i am at my wits end. I personally have tried everything. to no avail. you are also adding comments from 2025 above.
Haytham-C 4,300 Reputation points Microsoft External Staff Moderator

2026-07-20T01:38:51.6033333+00:00

Hello sheri s
I'm so sorry to hear that the issue still remains unresolve. As Norah inform earlier, we as a Microsoft Community moderator, can only help by sharing relevant Microsoft documentation and troubleshooting resources available to the public and related to your issue. Since we do not have access to internal diagnostic tools or product backend side, I can only recommend reaching out to Microsoft Support live chat again and once connected, please inform the supporting agent with all the step you've tried and your previous case number, and you can also request escalation on your case for further investigation if the issue still persists. I understand how frustrating this situation can be but with limited authorization, we can only guide you to the correct supporting channel.
Thank you for your understanding.
sheri s 0 Reputation points

2026-07-20T01:54:19.4933333+00:00

thank you. i do not know how much more time i have to waste on this, as i have told upteen people i will wait until the free trial is over to see if that shows up in my microsoft account as redeemed. my plan is to cancel the old subscription. that seems to be the majority consensus of people reading these forums although i have no faith in anyone. i will probably contact a lawyer and hope to start a class action for the poor support and aggravation i have received. it is corrupt what occurred to me and then no one responds with accurate information. for a company so large this should be the least respect someone should receive. ie which subscription they can safely cancel because of their errors and bugs. i am sure someone at microsoft has that answer. the chat does not work. i have tried 22 times. it only generates a case number. the calls i received back were from 2 phillipino people that hardly spoke English , did not have the answer, and then both hung up on me. Have another idea for me?
Ian-T 7,830 Reputation points Microsoft External Staff Moderator

2026-07-21T10:01:26.8033333+00:00

Hi

I completely understand how frustrating and disappointing this experience has been. I’m truly sorry, but as a community moderator, I have no further options available and cannot access or make changes to your account or subscriptions. Thank you for your patience and understanding
Alison A 5,210 Reputation points Microsoft External Staff Admin

2026-07-21T19:30:47.1066667+00:00

Hello @Desmond Kipenge and @sheri s ,

If you continue to experience any issues, please start a new thread so the community can provide assistance tailored to your situation. Out of respect for the user who originally asked this question, and in keeping with our Community Guidelines, we'll now lock this thread.

Answer 1

Microsoft 365 can run on macOS Ventura 13 only by using an older Office version.

Microsoft ended support for Ventura with Office version 16.101, released in September 2025. Newer Microsoft 365 installations and updates require macOS Sonoma 14 or later.

The support document reference you mentioned about OS 12 or later is for the recent certificate change, which is not separate issue.

Uninstall your current Ms365, then downgrade to version 16.101 by using this installer. https://officecdn.microsoft.com/pr/C1297A47-86C4-4C1F-97FA-950631F94777/MacAutoupdate/Microsoft_365_and_Office_16.101.25091314_Installer.pkg

Answer 2

Hi Amy Gallagher,

Sorry you’re running into this. Error 0x0 on a Mac is commonly related to saved Office sign-in or licensing information issues. Restarting alone may not clear that data.

First, confirm that the Microsoft account has an active Microsoft 365 license by signing in to Services & subscriptions. Make sure it is the same account being entered in Office.

If the license is listed, try the following:

Quit Word, Excel, Outlook, and all other Microsoft apps.
Open Spotlight, search for Keychain Access, and open it.
Search for Office, then remove the data license entry.
Run the official Office license removal tool for Mac. This method has resolved some similar Mac sign-in cases, so it is worth trying.

Note: The license removal tool only clears saved activation/licensing data on your Mac, it does not delete your purchase or invalidate your license. However, please make sure you still have access to the correct Microsoft account associated with your original Office purchase, as you will need to sign in again to reactivate it after running the tool.

Restart the Mac, open Word, and sign in again with the licensed account.

Please let me know how it goes after trying these steps, and I'll be glad to continue looking into it with you.

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Norah-L 8,155 Reputation points Microsoft External Staff Moderator

2026-07-15T05:04:55.6666667+00:00

Hello Amy,

Just checking in to see if you’ve had a chance to try the suggested steps.

Please feel free to share any updates.