IOS update with low space

I have got an IPad4 and with IOS 6 installed. I would like to install some new apps which need IOS 7 or higher, which push me to do the upgrade.

In the meanwhile, I have an old laptop. Once I upgraded it with a new SSD, which has only 240GB capacity. I installed dual-boot for Win8 and Ubuntu. Since I always play under ubuntu, I assign low space to windows, less to C volume. Which results into the issue mentioned below.

In the beginning, I was going directly upgrade via IPad itself. But it raises error, keeping telling me I don’t have enough space. The fact is, before I uninstalling my games I have more than 5GB free space. I also tried to reboot IPad but do no help though…

Reboot my laptop and enter windows using my user account (acutally I have another admin account). I installed itunes, connect IPad to laptop, follow the steps, click on “next”. Then error occurs, which telling me I have low space on this computer. I check and found really no space in C volume. The turth is I have installed itunes to D volume and also set “itunes media” path to D volume in preference setting. However, itunes update system still somehow using another path.

What is happenning is something like:

• Itnues will first download the firmware to: "%appdata%\Apple Computer\iTunes\ipad software updates"
• The appdata environ variable is setting per user in this case, I’m user account
• After downloading, itunes will extract the firmware to some temp directory. At this point, no free space on my laptop.
• If nothing bad haapen, itunes will copy the extracted firmware to IPad and it will handle all the process left.

The solution is:

• Download an application named junction, which seems to allow user to create some link file.
• Run cmd as admin account, run:
  • > junction -d <path>: to delete the existing link
  • > junction <link> <target>: to create a link to some directory else where. (NOTE: Don’t use %appdata% directory since you are now admin account)
• Now, after rebooting itunes I can download the firmeware to volume D. But the remaning issue is itunes will extract firmware to somewhere in volume C. I am not trying to figure this out since it will actually not stop the process and will be deleted/moved afterwards.

Finally, I get IPad working and the Apps installed. Woo.. It takes me some time because I wasn’t asking “google.com” at the very beginning but asking “baidu.comn” instead… Orz