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Running Outlook on the iMac causes the screen to flicker and eventually black out and reduce to half/split screen display.
If I don't run the Outlook app the Mac runs like clockwork.
With Outlook active, at some point the flickering begins and then gets progressively worse until the screen is completed fuzzed or it pops back to a half black screen (which continues to flicker intermittently - more often than not)
Whilst it sounds like a hardware issue (and I've ordered a new Mac thinking it was!) it appears to be tied to Outlook.
iMac (Retina 5K, 27-inch, Late 2015)
3.3 GHz Intel Core i5
8 GB 1867 MHz DDR3
AMD Radeon R9 M395 2048 MB
Mac OS 10.14.1 (18B75)
Outlook 16.19
Rebooting seems to clear it until we run Outlook again, then the cycle continues.
Using older versions of Outlook for Mac for personal email and calendar
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
Hi AussieFlem,
If you have any progress on this issue, just let me know at your earliest convenience.
Regards,
Marvin
Hi AussieFlem,
From your description, the issue only happens when Outlook for Mac client is opened. While from my test in the lab, I cannot reproduce this issue with the same Outlook client version and Mac OS version. So as you mentioned, the issue could be a hardware issue and running Outlook client could be a trigger.
Of course, you can try to download Outlook Reset Preference tool to reset the customization in Outlook > Preference and check if it helps. Meanwhile, it's a good idea to update to Office Insider version to verify if the issue still happens in version 16.20. If so, it would be better to change your iMac.
Regards,
Marvin