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I am having the same slowness, irratic, unstable issues with Thunderbird that I had 9 months ago. T-bird worked fine last sunday but now is unstable,

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  • Last reply by sfhowes

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Slow to download email, slow to respond or open email, slow or unable to delete email, "A script on this page may be busy....error message when trying to delete an email. I had similar problems before (9 mo ago) but they went away after dealing with McAfee. Thunderbird worked fine last sunday but when I tried to use it today I now have all these problems.

Slow to download email, slow to respond or open email, slow or unable to delete email, "A script on this page may be busy....error message when trying to delete an email. I had similar problems before (9 mo ago) but they went away after dealing with McAfee. Thunderbird worked fine last sunday but when I tried to use it today I now have all these problems.

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McAfee has been causing problems again this week, so the remedy remains the same:

https://wiki.mozilla.org/Thunderbird:Testing:Antivirus_Related_Performance_Issues#McAfee