Their webmail works fine, and when this account is added to the Windows Mail app, everything works perfectly. These are the common reasons why the IMAP folder is not syncing. To resolve the IMAP issue, I will explain different solutions in the upcoming section of the article. It's just a little bit technical, but we have an IMAP proxy that chooses from some different backend IMAP servers. If the user account ends up on an old IMAP server implementation (in that case f.i. a Cyrus imapd 2.4.17), IMAP Client of iOS 18 Mail app doesn't work. If the proxy directs requests to a newer IMAP server implementation (f.i Cyrus imapd 3.6.1), the iOS 18 Mail app works as expected, even the requests are handled by the same IMAP server proxy.

Why IMAP Folder is Not Properly Syncing?

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Chosen Solution

I work in a small company and for the past 2 weeks we've been having issues with customer support Outlook account. The account is used as IMAP in all customer support clients, every time you set up the mail in anyones computer disable faulty add-ins in Outlook it just sync 30-50GB ost files... And because of the size, this is making the mail simply stop working after one day of normal use, forcing the users to end outlook process to make the mail sync again properly... But only when you close/open the mail again.

IMAP folder sync issue in the new Outlook (moved emails not syncing to webmail)

If the server is down and you are experiencing issues, the problem IMAP folder is not syncing occurs. So, check the status of your IMAP server follow the steps below. These a general steps to check your IMAP settings in any email application. With the help of this, you can also ensure that the server settings are properly configured or not.

• It's just that the contents seem completely disconnected from what I see using webmail.
• I have half dozen mail accounts a few microsoft a gamil and some other ones and there is no difference they are all acting the same.
• I have not tried the add-on yet I am going to experiment.
• I use both webmail and Outlook desktop client to access my Gmail.
• If the server is down and you are experiencing issues, the problem IMAP folder is not syncing occurs.
• So, properly follow the above steps and backup your data from IMAP folders.
• So it must be something in IMAP protocol handling on the old server that makes the iOS Mail app go out of sync or crash the syncing mechanism on the iOS device.

My accounts in Mail app stopped to sync post update

Simply making a change in Outlook does not in and of itself mean that anything has changed in Gmail. For example, you can disconnect from the Internet and make changes. Outlook needs to explicitly reach out to Gmail and communicate Outlook Not Sending or Receiving Email the changes you've made. I would suggest that frequent changes to folder contents on multiple devices will make it go wrong. Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. This anomaly also occurs when using the hosting system (first type), using different names for inbound and outbound servers.





Mohit is a Microsoft Certified expert for all things Microsoft. He brings a unique perspective gained from nearly a decade of active participation in various IT forums, blogs, and social media. Through this hands-on experience, he has acquired knowledge in diverse domains like Microsoft 365 Cloud, On-Premise Exchange Server, AD, and Entra ID. At first, I was thinking it may be an issue with certificates, but it's not... I went to a bunch of online TLS tests and the mail server is fine and the certificates are trusted...