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Mail runs constantly

I have Macos Catalina 10.15.7. According to the activity monitor, Mail is consuming a huge amount of CPU time, often 120% or more (my MBP has two cores). The Activity window in Mail shows nothing except occasionally when it checks for new mail.


I tried rebuilding the Mail database, which seemed to fix some other issues (constant Moving Messages 1 of 101, with no progress evident), but it didn't change the constant running.


I'm beginning to think I've been infected with a cryptocurrency miner or some such nasty. How can I fix it?


MacBook Pro Retina

Posted on Feb 3, 2021 1:02 PM

Reply
Question marked as Top-ranking reply

Posted on Feb 4, 2021 3:35 AM

Judson Leonard wrote:

You don't understand. The activity window shows when a check occurs. I understand that, and it's not frequent. Mail is running continuously even when not checking for incoming mail.



To trouble shoot further you can:


—Try a SafeBoot https://support.apple.com/en-us/HT201262

Takes noticeable longer to get to the login screen, does a 5-15 minute disk repair before it fully boots up, and certain system caches get cleared and rebuilt, including dynamic loader cache, etc.

Login and test. Reboot as normal and test as caches get rebuilt.


In Safe mode third party system modifications and system accelerations are disabled, it removes malware, etc hampering smooth operation, however a reboot will put it back to normal mode.


This test will tell you if third party interference; extensions etc are not loaded in safe boot mode.


Similar questions

5 replies
Question marked as Top-ranking reply

Feb 4, 2021 3:35 AM in response to Judson Leonard

Judson Leonard wrote:

You don't understand. The activity window shows when a check occurs. I understand that, and it's not frequent. Mail is running continuously even when not checking for incoming mail.



To trouble shoot further you can:


—Try a SafeBoot https://support.apple.com/en-us/HT201262

Takes noticeable longer to get to the login screen, does a 5-15 minute disk repair before it fully boots up, and certain system caches get cleared and rebuilt, including dynamic loader cache, etc.

Login and test. Reboot as normal and test as caches get rebuilt.


In Safe mode third party system modifications and system accelerations are disabled, it removes malware, etc hampering smooth operation, however a reboot will put it back to normal mode.


This test will tell you if third party interference; extensions etc are not loaded in safe boot mode.


Mail runs constantly

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