Recently I noticed the Windows partition on my Windows Home Server was running critically low on space. Given that I store most of my data on separate drives and partitions, I thought this was a curious problem to suddenly run into.
One use of my Windows Home Server is to use it as an always-on iTunes server that stores all my content, and serves it on-demand to my Apple TVs, iPhone, iPad and computers. All of my iOS devices sync to the iTunes server. It was when I connected my iPad to the Windows Home Server and it complained that it was unable to save my iPad backup to the computer that I suddenly realised where all my C: partition space had gone. iOS device backups.
iTunes automatically chooses to save data to your User directory in Applications Data (AppData on WHS)\Roaming\Apple Computer\MobileSync\Backups.
While you can change where your iTunes library and content are stored, you have no control over the device backups storage location. My solution was to move “MobileSync” to my i: Drive (iTunes data drive) and then setup a Directory Junction from my Users directory to I:\MobileSync. A Directory Junction is a hard link to a directory. It in essence fools iTunes into thinking it’s storing data on C:\ when in fact it’s saving out to I:\. If you want to symlink to a directory using a hard link, then you should use the “/J” option.
1. I closed iTunes.
2. I moved my MobileSync directory (containing Backups folder) to my I:\ drive.
3. I then made sure MobileSync was removed from the old location.
4. I opened Command Prompt and issued the following command (replacing <username> with my own Windows login):
mklink /J “c:\Users\<username>\AppData\Roaming\Apple Computer\MobileSync” i:\MobileSync
5. A message was returning confirming:
Junction created for c:\Users\<username>\AppData\Roaming\Apple Computer\MobileSync <<===>> i:\MobileSync
6. I opened Windows Explorer and then browsed to the old MobileSync location and verified it was now linking to i:\MobileSync.
7. Finally I restarted iTunes, connected an iOS device and ensured it backed up data successfully to the new storage location.
Job done, C: partition rescued.