There are some differences in the OS between XP and Win7, so the profile is in a differently named place. But there are no differences in Thunderbird. I'm assuming you have installed Thunderbird on the Win7 computer. I assume you ran it for the first time to actually create a Profile, but have not added any mail accounts? If this is what you have done then all is ok. If you used imap mail account in XP computer then all your emails are stored on the server, so you can simply create a new existing mail account in Thunderbird on Win7 computer. Make sure it is an Imap mail account. If you used Pop or you had a load of emails in 'Local Folders' and you need to move a load of emails etc onto Win7 then here is info. Suggest you enable toolbars - all help articles refer to the toolbars and it just makes life easier: Click on 'Menu icon' > 'Options ' and select the toolbars. See first image below. Thunderbird profile folders are hidden files and folders. So if using windows search , you would need to include hidden files. This is where the thunderbird profile folder is located in Win7. * C:\Users\Windows user name\AppData\Roaming\Thunderbird\Profiles\Profile folder name\ Make hidden files and folders visible: Open a Windows Explorer window and choose "Organize → Folder and Search Options → Folder Options → View (tab) → Show hidden files and folders". see additional help: * http://kb.mozillazine.org/Show_hidden_files_and_folders To make it visible in Thunderbird: Via 'Menu Bar' 'Help' > 'Troubleshooting Information' Via 'Mail Toolbar' 'Menu icon' >'Help' > 'Troubleshooting Information' click on 'Show Folder' button see second image below. a new window opens showing the contents of your profile folder name. '''close thunderbird now - this is important''' Locate your backed up XP thunderbird profile folder name. Note: all default profile folder names are called: xxxxxxxx.default, where the x's are letters and numbers. open the backup profile folder name to see the contents. You need to copy all the files and folders - the entire contents of the backup profile folder name. Then paste them into the new profile folder name overwriting all the default files and folders. So your backup profile folder name and your new profile folder name have exactly the same contents - identical files and folders. See third image below as an aid to help you make sure you are looking at the correct folder - as an example, it shows all the contents of a profile folder name. There may be a few differences as there could be different preferences. eg: I have a 'chrome' folder because I created it, so it would not be in your default profile folder. Once everything is copied over correctly. Start Thunderbird.