Free Up Space by Moving Your iPhone and iPad Backups

Yesterday, I was attempting to update the firmware on my iPhone and iPad but was running into an error, specifically:

“iTunes could not back up the iPhone “Boyd’s iPhone” because the backup could not be saved on the computer.”

This was due to the C: in my computer reaching its capacity. Using a 128GB solid state drive meant I had to come to a decision about how to carve it up for the operating system and applications. I wanted to give enough space for applications so I split the drive roughly as follows:

• 40GB operating system partition (C:),
• 80GB application partition (D:).

The C: was always going to be a bit of a squeeze and I usually ran within about 2 or 3GB of maximum capacity. Things have been running fine for ages until yesterday. iTunes seemed to consume quite a bit of space in “C:\Users\<Username>\AppData\Roaming\Apple Computer\MobileSync” during the upgrade process and, in doing so, used up every last megabyte of space on the operating system partition.

Meanwhile, I had a 1TB hard drive as a data partition (E:) with some 830GB free. I thought to myself that surely there was a way I could move my iPhone and iPad backup to the E: as well as the temporary scratch pad used by iTunes during its upgrade.

I was right.

Without getting too technical, the default file system on modern Windows computers (which is NTFS – or New Technology File System) allows for something known as a “symbolic link”. A crude summary of this functionality is that you can repoint a folder (or file) that seems to exist in one location to another one in a completely different location.

So how did I do it?

Despite Windows 7 including a command line tool “mklink”, I used something called “Junction” created by Windows Sysinternals in 2007 and available here. It’s fairly straightforward to use too. Before I used it though, I renamed my existing backup folder @ “C:\Users\<Username>\AppData\Roaming\Apple Computer\MobileSync\Backup” by putting a “1” on the end and copied its contents across to a folder on the data partition.

Then, I opened an administrative command line and typed in the following:

• junction “C:\Users\<Username>\AppData\Roaming\Apple Computer\MobileSync\Backup” “E:\Backup\iTunes Backups”

Once I confirmed the iTunes wasn’t upset with using a directory symbolic link, I deleted the backups (and temporary files as a result of the failed firmware update) on the C: which raised my free space back up to 7GB.

Problem solved. As an aside, I have also found that iTunes is significantly faster as a result of enacting the above.

I’m sure there are other applications for the use of directory symbolic links but I thought this was a useful scenario in which others might find themselves.