Are you using IMAP mail accounts, or POP? How many messages do you have in your mailboxes? When did this problem start, and what have you done so far to resolve this issue?
I have occasionally had the same problem, except that in my case, it isn't when starting up Mail but after it has been running for a while. I have had to quit Mail and restart it to get back to normal.
In answer to the posed questions, I have only about 20 messages stored in my Mail folders. I have both POP and IMAP mail accounts. I haven't been able to do any problem solving thus far as Mail takes up all resources until I force a quit or on occasion, have powered off my iMac. On restarting, I have filed a report with Apple support.
I'm only using POP3 and POP3S.
Only 8 mails at this moment in the mailboxes.
A couple of thousand in Local Folders.
The CPU load starts when I open a video attachment.
Haven't done anything to resolve the problem.
Closing down Mail and reopening it helps but after the first video it 's back to 100% and more.
I think it started after a certain online update.
You shouldn't lose anything at all. I suspect they're still there, but Mail doesn't realize it. Try this:
1. Quit Mail if it's running.
2. Go to Home/Library/Mail and delete the Envelope Index file.
3. Restart Mail and let it import your existing messages; when it's done your mail index will have been rebuilt and your Sent messages should reappear.
Following all you advise, which is working great on itself, Mail still completely eats my CPU power AND MY BATTERY whenever it can: Actvity monitor says Mail 99.999% usage.....
Guys, what in earth is going on?? This can't be true, is this the reliable Apple I used to meet just a couple of months ago?
I share your opinion.
Where has my reliable Mac gone?
I quited Windows and Linux to have a stable platform.
The problem is still there.
Just did the test. I only opened Mail and Activity Monitor.
Without any reason the CPU goes to 99,xx % only for Mail after a while.
Quiting mail helps but after relaunching it, the problem re-appears.
There's obviously something more serious going on with your Mac, so we only have a few things left to try before resorting to something drastic. So let's try this:
1. Quit all running applications.
2. Go to Home/Library/Caches/Mail and delete everything inside that folder.
3. Go to Home/Library/Caches/MetaData and delete everything inside that folder.
4. Go to Home/Library/Mail and delete the DefaultCounts, and LSMMap2 or LSMMap3 files;
remove the MessageRules.plist file.
5. Restart Mail and see if it still takes all your CPU cycles.
When I use Quick Look and double click on the preview of the movie QuickTime launches and the CPU is off to almost 100% (for Mail app)
Hmmm…then I wouldn't use the Quick Look function if you can avoid it. And if Mail no longer behaves badly, I'd put the MessageRules.plist file back in Home/Library/Mail and restart Mail to be sure the problem doesn't start again.
I'm getting really sick of it.
Today Mail ets the CPU immediately after opening it without any clear reason.
Guess I have to go to the drastic solution: Re-install like in the "good" old days.
Thanks for thinking together with me.
I would do an Archive & Install with the Preserve Users and Network Settings option. This will reinstall Mac OS X 10.5, preserve all your programs and settings, and put the old installation into a folder named Previous System, which you can then delete. You would then need to either download the 10.5.4 or 10.5.5 Combo Update and install it, or rely on Software Update; then Repair Permissions, restart your Mac and with any luck you should be back to normal.
For some unclear reason, Mail has not crashed for a while, and I did not delete anything in Mail nor did I perform the actions Mulder suggested (thanks for that anyway, any help and effort much appreciated!) In general, one of my MacBook Pro's - the one with most apps - keeps crashing on daily basis.
Somehow i had the same problem. Mail started to use about 99% percent of the cpu and the vents got noisy.
I realised that it came up the first time, after i was receiving a mail with a wmv-file attached. I just deleted that mail and cleaned the trash.
Everything is fine again.
Maybe this easy solution helps to some of you.
