I'm planning to buy a Western Digital My Passport 4TB external HDD. In the official page, it says that it's compatible with Windows 7/8/10, and that use for any other OS's requires reformatting. Thing is, I want to buy this HDD so I can backup my files from my old Windows XP installation, then format the PC and transfer the files onto a newly formatted Windows 7 one. What problems will I encounter by using this drive on 2 different OS's? Is there a fix? If I use only the most basic drivers for this HDD, will I have an issue?