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25105 Views 105 Replies Latest reply: Jul 2, 2013 1:22 AM by Peacekeeper RSS 1 2 3 ... 11 Previous Next
aaronmefford Newcomer 35 posts since
May 8, 2012
Currently Being Moderated

Dec 19, 2012 6:37 PM

McAfee and Thunderbird Do Not get along

I have been having an issue for quite sometime with McAfee on one of my machines where mcshield.exe would jump to 50% or 100% of the CPU (dual core).  Finally today I realized why it was sporadic.  It only occurs when I am also running Thunderbird and accessing my email.  I have seen a large number of threads about slow startup times with Thunderbird due to McAfee, but my issue is more than that. 


If I have Active Scanning on and access any message within Thunderbird, McAfee mcshield will consume a full processor and Thunderbird will become slow to respond intermittently windows reporting it as an unresponsive process.  If I click on another message in a different mail account and another mail message, then McAfee will consume the other CPU and put the machine at 100% making Thunderbird and nearly anything else unuseable. 


The problem is clear.  McAfee is convinced it needs to scan the Thunderbird database everytime it is modified.  Why this does not happen for Outlook is beyond me, but I assume was some backroom deal.  I use IMAP and my mailboxes are massive, one is over 4 Gigs.  This is no longer uncommon with mail services like GMail being available.  If McAfee thinks it needs to rescan that 4G file everytime it is modified, it is no wonder that my machine grinds to a hault everytime I receive, read or delete a message.  I tried adding the Thunderbird profile folder as an exclusion.  This will probably speed up my periodic full scans, but seems to have absolutely no effect on the Real Time Scanning.  If I disable Real time scanning everything is great until it turns back on.


I do not love the idea of disabling realtime scanning but it seems I may have no other choice.  Is there anyway to tell McAfee to ignore certain files?   There must be as it does so for Microsoft Outlook (which has mail databases of similar size). 


Once again I am wondering if it is just time to scrap the AV software I have used and trusted for 15 years.





Windows 7 Home Premium Service Pack 1 64 bit

Intel Core 2 Duo E7200 2.53GHz

4.0 GB Ram

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