This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Thunderbird is using 12.5GB of disk space. How can this be reduced?

  • 3 replies
  • 3 have this problem
  • 1 view
  • Last reply by christ1

more options

I took a look at this thread: https://support.mozilla.org/en-US/questions/999525?esab=a&as=aaq

However, I don't see any nstmp files, so the solution doesn't transfer.

I use Thunderbird to manage six email addresses. At present, Thunderbird is using 12.5GB in my AppData folder, which is roughly an eighth of my hard drive (SSD). I either need to reduce that or force Thunderbird to store these on a different hard drive. How can I do either?

I took a look at this thread: https://support.mozilla.org/en-US/questions/999525?esab=a&as=aaq However, I don't see any nstmp files, so the solution doesn't transfer. I use Thunderbird to manage six email addresses. At present, Thunderbird is using 12.5GB in my AppData folder, which is roughly an eighth of my hard drive (SSD). I either need to reduce that or force Thunderbird to store these on a different hard drive. How can I do either?

Chosen solution

first and foremost... Compact your folders. That is the only time space is freed. Deleted mail is marked as such but not purged until the compact occurs. So, File menu (Alt+F) > compact folders

Second move your profile, See for locating your profile https://support.mozilla.org/en-US/kb/profiles-tb See for moving your profile using the profile manager. http://kb.mozillazine.org/Moving_your_profile_folder#Firefox_Thunderbird_and_SeaMonkey_2

Read this answer in context 👍 1

All Replies (3)

more options

Chosen Solution

first and foremost... Compact your folders. That is the only time space is freed. Deleted mail is marked as such but not purged until the compact occurs. So, File menu (Alt+F) > compact folders

Second move your profile, See for locating your profile https://support.mozilla.org/en-US/kb/profiles-tb See for moving your profile using the profile manager. http://kb.mozillazine.org/Moving_your_profile_folder#Firefox_Thunderbird_and_SeaMonkey_2

more options

Compacting folders does nothing for me -- I don't know why. I compacted them today for the first time in about a year, and the folder size remained unchanged. I don't generally delete emails, so that's likely why, but that doesn't mean I need to keep local copies of 12.5GB of emails.

I'll try out moving the profile, thanks!

more options

You complain about the size of your profile, but at the same time you're saying you don't delete any messages. What's not entirely clear to me is whether you actually want to store emails locally in the first place. If so, I'd move the entire profile to another disk (assuming you do have one). http://kb.mozillazine.org/Moving_your_profile_folder_-_Thunderbird