I am looking to copy Thunderbird to a new machine but it's not as simple as it should be because I have Thunderbird data in multiple places. From Help/Troubleshooting Profiles, I get: Default Profile yes Root Directory C:\Users\Randy\AppData\Roaming\Thunderbird\Profiles\ohig3f3m.default Local Directory C:\Users\Randy\AppData\Local\Thunderbird\Profiles\ohig3f3m.default The root directory is 1.37 Gb The local directory is 8.23 Mb I also have d:\data\thunderbird which is 14.7 Gb. There is no Profiles subfolder here. The two profiles folders show ohig3f3m.default was updated today. All three folders show files as recent as today. The file sizes shouldn't be surprising. I have saved emails back to 2007 and I'm a prolific email writer. I'm guessing that some time years ago, with a much smaller main hard drive, there was an option to save Tbird data to a different location than the default. So I set it to be on my D drive. So what do I do now? I could copy all three directories to a new machine in the same locations. I think that should work. But is there some way I could or should simplify things, or should I just leave well enough alone.