u/1d0n1haveaname

Is it possible to merge the free space from my D: drive into C:? My C: drive (199 GB) is completely full, while my D: drive (213 GB) has about 198 GB free. I want to increase the size of C: by using some or all of the unused space on D:, preferably without reinstalling Windows or losing any data. Is this possible, and what's the safest way to do it?

Update: issue solved. I ran sfc /scannow, which repaired some corrupted system files. Then I used AOMEI Partition Assistant to move the required partitions and extend my C: drive. Everything completed successfully without any data loss. Thanks to everyone who took the time to help!