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Lately Office 365 Outlook has a super-long delay in receiving emails. The same emails arrive on my phone normally (immediately). This has been reported by others, but I haven't found any solutions for the problem.
Restarting Outlook and/or the computer does not help.
I've tried checking all the settings and removing old emails and settings that might have caused the problem. That helped for about a week, then it started happening again today.
There are too many acceptable email clients on the market to have to put up with this kind of failure from the #1 email program. Is the problem that Microsoft does not care anymore or that they can't figure it out either?
Using Classic Outlook on Windows for personal email, calendar, and contact management
Locked Question. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
Which version of Outlook are you running?
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Here it is 2026 and it takes over 30 min to receive an email. Someone does NOT know what they are doing and needs to be let go. OR just FIRED.
@James Bruce, you have replied to an old thread. I recommend that you ask a separate question so that it gets more attention. Use the Ask a question button on the Q&A page. Be sure to include information that is relevant to your situation (type of account, version of Outlook etc.). Good luck. (The current thread will be closed.)
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Having this problem as well, MS 365 Business Basic so not using the desktop app, using Outlook online/web browser.
@Steve T, since you mention that use Outlook web, are you seeing sync issues between Outlook web and Outlook on your phone, for example? Please elaborate.
I'm doing this on behalf of a client. Phone also seems to be "sporadic". Do you know how to switch off Cached Exchange Mode if using Outlook online? Answers from web searches seem to be referring to the Outlook desktop app.
As far as I know, the setting you mention only exist in the classic Outlook desktop app.
Also, the sync problem as discussed in this thread appears to be primarily with the desktop app.
Since your client is having trouble with synchronizing between other versions of Outlook, I recommend that you start a separate thread. Use the Ask a question link at the top of the forums page.
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Hello Larry,
This problem has been reported by many users and is often linked to Outlook’s desktop app struggling with synchronization, especially when using Cached Exchange Mode, outdated add-ins, or corrupted local data files (.OST). It can also be caused by antivirus software, network instability, or even Outlook being out of date. Some users have found relief by disabling Cached Exchange Mode, repairing their Office installation, or rebuilding their Outlook profile.
Others have had success using the Microsoft Support and Recovery Assistant (SaRA) tool, which can diagnose and fix sync issues automatically. You can also try manually forcing a sync by pressing F9 or using Send/Receive All Folders, and checking your account status under File > Account Settings.
This might help