Windows is installed. So the best ways to manage your system is to use the C drive for the OS only and use D or other drives for applications and data. That way only C gets reformatted on a clean install of Windows. Email is a different situation. Thunderbird is an email client which means it's software that manages email. There are 2 type of email POP3 and IMAP. POP3 is email where you receive email on you providers server and you download the emails thru your email client to you PC. Most POP3 emails have a switch in your configuration that allows you to delete the mail once it's downloaded to your pc. I myself have a POP3 account and I uncheck this box so I get the same emails on multiple devices. ThenI have to manually login through a browser and delete the email from the server. IMAP doesn't download the emails to your PC and your client views them on your providers server. AOL, Yahoo and Gmail are like this. So when you delete your actually deleting on the server. So if you have IMAP email you would have to configure the provider then view the email that weren't deleted.
I have a Surface Pro 3. There were many problems with it and I finally re-installed Windows 10. I followed the instructions the MS support rep gave me. I knew that some apps would be removed, but it did not occur to me that the data would disappear. I was hoping to install a replacement app and then upload the old contents. For example, my One Note contents are completely gone. The e-mails I had saved in Thunderbird are gone. So I can reinstall the app, but have lost data. I looked under Windows.old and app data/roaming/applications... and I don't think there is anything there that will help. I found a profile folder for Thunderbird, but there wasn't anything there. Is it possible to recover my e-mails and documents that the installation wiped clean? I had done a full backup before I started this process, but it's blank. I'm willing to take the Pro to a pc guru if anyone thinks there is hope. Your comments will be appreciated.

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