Turbotax doesn't like to not be on the C: drive, it;s just a thing. The best thing to do is to uninstall the program then reinstall it in the normal way. Your tax data is in a separate file (a document, usually named something like "Smith 2024.tax2024") and I think that can live anywhere. You can save it on a flash drive, or move it manually to your Documents folder on the C: drive.