What are you trying to achieve in the first place? Typically people want to check for new mail more, and not less frequently.

Also, what is your account type - POP or IMAP?

Configuration is IMAP. I want to get my emails at a set interval, for example each hour or half hour. I don't want emails every 2 minutes.

IMAP doesn't work that way. The server is live and messages may arrive.

At the top right of the Thunderbird window, click the menu button ≡ > Account Settings - Server Settings

Check the option "Check for new messages every x minutes" and select the desired interval. Un-check the option "Allow immediate server notifications when new messages arrive"

Christ1 is correct, but my experience has been spotty with IMAP.

Thanks David and Christ1 for your suggestions. I'll see how it works with IMAP. I don't think my email accounts even allow POP now.

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