Thunderbird – Error Copying to Sent Folder

thunderbirdA user has complained about a problem with Thunderbird for a long time. The problem is that sometimes when the user sends a message, the message got sent but then a pop up window shows up saying “Error Copying to Sent Folder”. I thought it’s related to the mail server and did not pay close attention to it.

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I did a google search on this problem yesterday and found this page. It looked promising, so I tried it on my user’s machine. The user has yet to encounter this problem after the changes. Here are the steps for Thunderbird 2.0.0.23.

  1. Click on Tools -> Account Settings.
  2. Click on Server Settings under your account and then click on Advanced.
    tb-copy-1
  3. Change Maximum number of server connections to cache to 1. The default is 5, just in case you want to change it back.
    tb-copy-2
  4. Close all the dialogs and restart Thunderbird.

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