How do I change the location of my WinXP application data?

March 15, 2008 11:08 AM

How can I move application data to another drive?

I'm using WinXP. I followed advice to use 2 partitions to make backups easier. I have Windows and my applications on a smaller C: partition and my data on a larger D: partition. The problem is that my application data is on my C: drive and it is filling up. So I need to move the application data to my D: drive.

I have recreated the folder structure on the D: drive and copied all of the application data there (I'm talking about the data in C:\documents and settings\username\Application data\, where username changes for each of the login profiles).

The webpages I've found say that at this point I should go to regedit and change 'HKEY_CURRENT_USER\software\Microsoft\windows\CurrentVersion\Explorer\User Shell Folder\AppData' from value 'C:\documents and settings\username\application data' to 'D:\documents and settings\username\aplication data'.

However, at that regedit value on my computer, it doesn't say 'C:\documents and settings\username\application data'. It says '&USERPROFILE%\Application Data'. So I'm not sure what to change the value to. There is only one value here, so what do I do with the multiple user accounts? I obviously don't want to mess up the registry.

Advice, please? Do I indeed just change this value to something? Will I have problems with specific applications finding the original data? Is there another, better strategy? Thanks for the help.

posted by underwater to computers & internet (3 comments total)

That is theoretically possible and preferable. In a perfect world. But badly done apps break it because they have C: hard coded in. It may be more trouble than it's worth.
posted by gjc at 11:16 AM on March 15, 2008

I think a better strategy is to use tools to make your C partition bigger and your D partition smaller. That's really the only fool proof plan.
posted by mmascolino at 11:24 AM on March 15, 2008

I'd search your registry first, as gjc states, to see if any applications are hard-coded to the Application Data folder.

&USERPROFILE% is simply an alias Windows uses to reference the folder that is related to your account and would be translated to C:\documents and settings\username\ in your example. Theoretically, you could simply replace it with the literal path to your new Application Data folder.

Given the risk of hard-coded references, however, I'd suggest trying a "symbolic link" (NTFS Junction) instead of mucking with the registry. What you'd do, basically, is copy your Application Data folder to a new volume (it could simply be D:\Application Data), rename the old application Data Folder (to be safe) and then create a symbolic link that tells the file system that all requests for the original path should be transparently directed to the new location.

There is a command line tool from Microsoft/Sysinternals that I've used in the past for critical folders. I also came across a program called Junction Link Magic that has a GUI.

Since it's an operational windows folder, there's a slight chance that you'll get errors in the process that would require a boot into DOS to make the change -- but I tried renaming my own Application Data folder just now and it worked, so doing the whole process in Windows may be possible.
posted by VulcanMike at 12:57 PM on March 15, 2008