Outlook on Mac is continually uploading to the Internet. How can I stop this?

Question

My wife runs Outlook on her Mac. Every time we start it up, or it is running, it is continually uploading to the Internet and totally ties it up. I don't think that it is uploading emails, as she is not that busy. I scanned the app file for viruses and found nothing. We are in the Bay Area, and Avast shows that Outlook is connecting to Miami, or other weird places, like Germany. I am thinking that it is running as a bot. If not, how can I get it to stop uploading? I am not sure which version she is running, but I just checked for updates and it came back saying this is the most recent version.

At a different Microsoft forum, a response said that Outlook constantly syncs with the web. If this is the problem, how can I turn it off or moderate it? The fact that it grabs nearly all of the web bandwidth (we get 44MB on our Internet), continually, just seems crazy to me. Help please.

Answer 1

Hi @Roland P

Thanks for your follow up, you may try some following initial steps:

Check your mailbox size: If your mailbox is too large, it may take a long time to upload all the emails. You can try reducing the size of your mailbox by archiving old emails or deleting unnecessary ones.

You can try adjusting your sync settings to only sync the most recent emails or to only sync when you manually request it. More information, see: Outlook for Mac crashes unexpectedly on startup or during mail synchronization - Microsoft Support.

Repair your Outlook profile: You can try repairing your Outlook profile by going to the Help menu and selecting "Troubleshooting Information" and then selecting "Repair Profile."

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Answer 2

Hi @Roland P

Thanks for your reply!

It looks like you're dealing with some unusual network activity from Outlook, and it's understandable to be concerned about potential security issues.

According to my research, Avast Security is a product that offers a range of products designed to protect your device and online privacy. However, since it is a third-party product, it is important to guarantee that it is a safe channel to download. It is recommended that you disable it and then check if there is any abnormality in Outlook.

Also, for the security issues of the Outlook desktop client, I suggest you investigate from the following questions:

View email activity: Check for sent items and any unusual email activity that may indicate that your account has been compromised.

Check for plugins and plug-ins Outlook add-ins can sometimes cause excessive data usage. Disable any non-essential plugins.

Check your account's trusted devices. To remove trusted devices, go to the Security basics page, select more security options, scroll down to Trusted Devices, and then select Remove all the trusted devices associated with my account.

Recreate a new profile. Manage profiles or identities in Outlook for Mac - Microsoft Support.

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Answer 3

Hi SokiGuo,

The problem is solved.

I have to apologize, as one of your posts basically had the solution in it. My unfamiliarity with the Mac version created some difficulty for me. You had suggested to check the mailbox size. I had checked the inbox and sent boxes, but somehow I missed the trash box. It turns out that there were over 1900 messages in it. We deleted these messages and the problem came to an end. I guess Outlook was trying to synch the trash between her Mac and the cloud. Thanks again.