mklink error: Cannot create a file when that file already exists

the syntax is incorrect. mklink has the following synatx:

mklink [options] <Link> <Target>

Target is the file/folder that exists, and Link is the created one that links to the target.

so the command should be:

mklink /D "E:\Apple Computer\MobileSync\Backup"  "C:\Users\odellt1\AppData\Roaming\Apple Computer\MobileSync\Backup"

See the Microsoft Documentation for mklink usage.

The simply way is delete the Backup folder in Original apple folder backup (in C:\ driver) When we run the command:

mklink /J "%APPDATA%\Apple Computer\MobileSync\Backup" "E:\iTune Backups"

windows will create a link shortcut Backup in C:\ driver.

I had the same issue with the "file already exist error", until I used the "%AppData%':

mklink /J "%APPDATA%\Apple Computer\MobileSync\Backup" "E:\iTune Backups"

Junction created for C:\Users\Me\AppData\Roaming\Apple Computer\MobileSync\Backup <<===>> E:\iTune Backups

Note: Make sure you use straight quotes, otherwise you get a syntax command error.