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Thunderbird is slow, can't open e-mails, is non-responsive and crashes constantly.

  • 10 replies
  • 8 have this problem
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  • Last reply by hholmstr

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I just purchased a new computer with Windows 7 Professional 64bit. I downloaded Thunderbird and imported my old user profile as I have always done in the past. Thunderbird runs unbelievably slow. I will double click to open an e-mail and it takes 1 to 3 minutes to open it. Thunderbird shows a "Not responding" warning almost every time this happens. Also, if I delete a message it takes about 45-60 seconds for the program to respond and move the message to the trash. Opening and new message or old messages and deleting or moving emails to a different folder are when the problems occur. Writing a new message doesn't seem to be a problem. It is not my internet connection (the connection doesn't show any time-outs and no other users in my office have had this problem). What is the solution? If it can't be fixed then I will simply stop using Thunderbird as my e-mail program.

I just purchased a new computer with Windows 7 Professional 64bit. I downloaded Thunderbird and imported my old user profile as I have always done in the past. Thunderbird runs unbelievably slow. I will double click to open an e-mail and it takes 1 to 3 minutes to open it. Thunderbird shows a "Not responding" warning almost every time this happens. Also, if I delete a message it takes about 45-60 seconds for the program to respond and move the message to the trash. Opening and new message or old messages and deleting or moving emails to a different folder are when the problems occur. Writing a new message doesn't seem to be a problem. It is not my internet connection (the connection doesn't show any time-outs and no other users in my office have had this problem). What is the solution? If it can't be fixed then I will simply stop using Thunderbird as my e-mail program.

Chosen solution

Uninstalling McAfee seems to have fixed this problem (and a few more with other software). THANK YOU!

Since I didn't want to be without any virus protection I put Microsoft Security Essentials (Free from Microsoft) and it doesn't interfere with any of my programs or software.

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All Replies (10)

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Might I guess your new computer came with McAfee?

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Yes! I hate it and I am trying to remove McAfee but it doesn't seem to be working. Please tell me there is a solution?

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Disable email attachment scanning. Change scanning to be programs and documents only.

The easiest way is go to their web support get a chat session going and they will fix it for you.

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Thank you! I will try that.

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Chosen Solution

Uninstalling McAfee seems to have fixed this problem (and a few more with other software). THANK YOU!

Since I didn't want to be without any virus protection I put Microsoft Security Essentials (Free from Microsoft) and it doesn't interfere with any of my programs or software.

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I have already disabled mcafee scanning of attachments, but the problem persists.

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RDubey1903: The only solution that I found was to completely UNINSTALL McAfee. I did that and then put Microsoft Security Essentials on my computer and I have not had any problems with Thunderbird since. Everything is working perfectly. Microsoft Security Essentials is free and it scans my computer constantly and gives me warnings just like McAfee would.

If you are using McAfee as your virus protection and you want to keep using it then I would suggest you switch to using Outlook rather than Thunderbird for your e-mail.

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The fixes for McAfee are numerous. Excluding the Thunderbird profile folder from scanning is probably the one you need. But there is a possibility that your need to set it to scan programs and documents only. Both have been reported to fix slowness.

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I had the same issue and called McAfee. On the second call, I got a tech who knew what he was doing. If you are using McAfee Internet Security like I am, go under "Real Time Scanning" from the home page. Click on "Settings." Scroll down until you see " These Attachments and Locations." UNCHECK "Email attachments". Save and exit. I rebooted and then tried Thunderbird, and everything worked perfectly again!

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I used Thunderbird for years without problems until I installed McAffe. Since then Thunderbird has been slow, crashing and almost useless, no matter what I tried. Yesterday I returned to Norman for virus protection, and voila: Thunderbird immediately returned to normal!