Yes you can and this has been answered many times. However, let's try once again.
Assuming that your files are on C:\My files\Music\ and you want to move them to D:\Music\.
Option A
- Back up the media files and the library
- Disable the Auto-Importer
- Select all files > right-click > Library Tools > Find and Replace > Tick only: Filename (path), Find what: C:\My files\Music\, Replace: D:\Music\
This will move the files and keep the library up-to-date. This may be unsafe if the OS or MC crashes. You may end up with partially unsynchronized library.
Option B
- Back up the media files and the library
- Disable the Auto-Importer and close MC
- Move the files with Windows Explorer. If you want to only copy and keep the old files too you must rename the old base folder after copying. (Rename all base folders if you have more than one.)
- Open MC, select all files > right-click > Library Tools > Find and Replace > Tick only: Filename (path), Find what: C:\My files\Music\, Replace: D:\Music\ (Since the old files are not available MC will make the changes only in the database. This is very fast.)
This is safer because Windows Epxlorer does only one thing. It moves the files. It does not alter the database at the same time.
Option C
Assuming that the source is for example D:\Music\ and the target is E:\Music\ and you don't have other files that you can't move on these drives.
After copying or moving the files outside MC change the drive letters with the Windows Disk Manager. For example: change D: to F: and E: to D:. No library changes are needed.