Outlook app for iOS Stopped Working

Question

My Outlook App for my iPhone 12 running iOS 26.3.1 stopped working early in March. It has run well for many years.

I have not been able to reestablish the IMAP account.  The Outlook App is working on my older iPhone and iPad.  My IMAP email account is hosted by Dreamhost.com and I am suing there recommended configuration settings which include:

Incoming IMAP:  dreamhost.com - Port 993 with SSL Security

Outgoing SMTP:  smtpdreamhost.com - Port 587 with STARTLS Security

I have tried a variety of Ports just check out if that is the issue – it is not.

I also deleted the Outlook App from my iPhone and reloaded it to the iPhone

I continue to get the message :  "Unable to log in to. Log in failed. Please Check your IMPA Server Settings and Try Again" 

I am able to set up the IMAP email account using the above settings for the iPhone native iOS Mail app. 

I have had excellent support from Dreamhost – but they have no insight of what is going on with the Microsoft side of the transaction.  They have gone as far as the can, and we both think it has something to do with the process the Outlook App uses that goes through Microsoft cloud and then on toe Dreamhost – where the iPhone native iOS Mail app goes directly to Dreamhost.

 Does anyone have thoughts on how I can reestablish my IMAP account on the iPhone Outlook app?

Answer 1

Hi Frank Petrus, 

I can understand why this is frustrating, especially when this same IMAP account had been working in Outlook for iOS for years and the native iPhone Mail app is only a temporary workaround for you. 

Based on the information you shared, it seems that you may have entered the incorrect incoming and outgoing host names. I checked the DreamHost IMAP setup, and it shows that the incoming and outgoing server names should be:

Please note that this is a third-party resource provided and maintained by DreamHost, so its content is outside Microsoft’s management.

For more information, please visit https://help.dreamhost.com/hc/en-us/articles/214918038-Email-client-configuration-overview

Just a quick question, are you using any VPN, iCloud Private Relay, or mobile security/filtering app on the affected iPhone? 

In the meantime, please try the steps below: 

1. Add the account again using manual/advanced setup 

• If Outlook offers automatic detection, please switch to the manual / advanced setup path and enter the DreamHost settings directly.  

2. Re-enter the server names exactly as below 

• Incoming IMAP server: imap.dreamhost.com 
• Port: 993 
• Encryption: SSL/TLS 
• Outgoing SMTP server: smtp.dreamhost.com 
• Port: 587 
• Encryption: STARTTLS 
• Username for both: your full email address 
• Password: your mailbox password 

3. Try on a different connection 

• Please test once on Wi‑Fi and once on cellular data. If you are using VPN / Private Relay / filtering software, please temporarily disable it and try again. 

4. Restart the iPhone, then test again 

• After restarting, open Outlook and try adding the IMAP account again with the manual settings above. 

While my initial response may not fully resolve the issue, I truly appreciate your cooperation as we work together toward identifying the most effective solution. Thank you so much for your understanding. 

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