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adamshore Author

Level 1

0 points

Mail running +100% of my CPU!

Every since I installed Snow Leopard and then Lion on Sunday, Mail has been taking up over 100% of my CPU. Even when I go offline, when I turn off my wireless, it runs over 100% of my CPU.

I run a lot of RSS feeds through Mail - a couple hundred. I like seeing web posts as I see mail - to have everything in one stream. This was never a problem before I installed Snow Leopard and Lion - Mail was fast before. Now when I open "Activity" it seems to check feeds much slower than before.

I turned off all sharing, no MobileMe. It's making me feel like I'm working underwater, everything is sluggish and slow, mail is constantly not responding, and I get the spinning wheel all the time. Why is this happening?

For what it's worth - Address Book is incredibly slow as well.

MacBook Pro, Mac OS X (10.7)

Posted on Jul 26, 2011 1:35 PM

39 replies

notrobot

Level 1

0 points

Oct 25, 2013 9:37 AM in response to Monkey Cat

This worked for me also. Thanks!

rinjin

Level 1

4 points

Oct 26, 2013 1:18 PM in response to A.dickey

This seems to have fixed the problem for me too. Whew.

Thanks!

phybsz

Level 1

0 points

Oct 28, 2013 7:38 AM in response to ramarsha

Thanks!!!

Mitranim

Level 1

0 points

Dec 17, 2013 3:38 AM in response to A.dickey

My Mail used to run on 30-40% CPU constantly, running keychain first aid instantly dropped it down to 1%. Thanks for the tip!

Mitranim

Level 1

0 points

Dec 17, 2013 4:19 AM in response to Mitranim

...A-a-and then it's back at 40-50-60% again. This time keychain repair has no effect. The problem must be something else. This is very sad, as it makes Mail useless for those who aren't plugged into a wall socket all the time and / or don't want to have their hands fried by the machine...

Jan 6, 2014 7:53 AM in response to A.dickey

This totally fixed it for me too, great find. Postbox went from 100% to around 1% after I ran Key Chain ~ First Aid. Turns out there were incorrect mail passwords and ports in Keychain, must have caused Postbox to try all of them or something.

Thanks!