Offline Files

Moving the CSC

Tested on Windows Vista and Windows 7.

Are you tired of having the offline files client-side cache (CSC) feature of Windows taking up all the free space on the system disk? Well, move the bloody thing. As far as I can tell Microsoft does not provide an automated way to do this. So it’s off to hack the registry. I tend to use the G: drive to store CSC files on my Windows clients, so will use that in the examples below.

First, make sure the CSC has not already been moved. Fire up regedit.exe and navigate to this key:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\CSC\Parameters

If there is a value named CacheLocation then the CSC has already been moved and you might want to keep the CSC at this custom location. In the absence of this key Windows keeps the CSC files here:

%systemroot%\csc

which usually equates to:

C:\Windows\csc

Important: These instructions describe how to erase all of the existing offline files that have been cached to your PC. After specifying a new location for the CSC the files will be copied again from their source network location into the CSC. Since I usually move the location after a new PC install or after repairing/rebuilding a hosed PC I don’t care about the current contents of the CSC. If you do care about the current contents then do not follow these instructions!

Also, if you already have offline files enabled then be sure to run a sync against all of your offline directories so that any changes to any of the files that you have made on your PC are propagated back to the server. If you have not done this and you have changed files on your PC and then follow the instructions on this page you will lose any changes to those files that you made on your PC. You have been warned!

Having said that[1], you might want to create a system restore point before proceeding (Control Panel → System → System Protection tab → Create button).

Now, let’s change the location of the CSC files. First create the directory that will contain the CSC (we are using G:\csc in this example). The, go to the registry key above and create the CacheLocation subkey if it does not already exist. Point it to the directory you want to store the CSC files, in this format:

\??\g:\csc

Now create a subkey (of type DWORD) in this same registry key called FormatDatabase and set its value to 1. This subkey will cause any existing CSC directory to be deleted on the next boot, and the subkey itself will be removed from the registry on the next boot.

Reboot the system. After the reboot get rid of any existing CSC files:

takeown /r /f %systemroot%\csc

rd /s %systemroot%\csc

Now go to each directory you want to keep an offline copy of and set them to Always available.

Done!

References

  1. Moving the Offline Files Cache in Windows Vista

    1. The procedure described here has worked fine for me with Windows Vista, but not with Windows 7 (see the next reference).

  2. How to Move Offline Files Cache in Windows 7?

Footnotes

[1] While writing these instructions (11/23/09 9:00 a.m.), I am listening to Margery & Jim on the radio. Jim “the Red” Braude of course uses this expression all the time. And having spouted the phrase yet one more time, Margery plays a bit from last night’s Curb Your Enthusiam where L.D. and Jerry Seinfeld do a great bit about the vapidness of this phrase. Please do not use this phrase in your speech or in your writing!