There are two versions of SyncBackPro and SyncBackSE: the standard 32-bit version and the new 64-bit version. SyncBackFree is only available as 32-bit versions, as are all versions of SyncBack older than V8.
There are important differences between the 32-bit and 64-bit versions. If you are unsure which version to use, you should continue to use the standard 32-bit version (or whichever version you have installed). Do not install both the 32-bit and 64-bit versions of SyncBackPro or SyncBackSE as having both installed at the same time will cause problems.
If you want to switch from 32-bit to 64-bit you should:
1. Export your profiles from the 32-bit version (Note: If you have Groups, both member profiles and Groups must be exported. Disable option "Only show groups and profiles not in a group" under: burger menu > Preferences to see all nested profiles. Press Ctrl+A to select all profiles.) You can refer to this article for profile Export/Import instructions.
2. Uninstall the 32-bit version. If you are prompted with Would you like to keep your profiles and settings? then click Yes.
3. Install the 64-bit version.
4. Start SyncBack. If you were prompted to keep your settings in step 2, then you shouldn't need to do anything. All your profiles and settings will be as they were in the 32-bit version. However, if you were using an older version of SyncBack then you may now need to Import your profiles.
This process is the same as moving an installation from one computer to another.