Cleanmgr

Reclaiming Space: How to Clean Up WinSxS on Windows Server 2008 R2

Posted on May 4, 2015 Updated on April 15, 2026

The C:\Windows\WinSxS directory is notorious for growing over time as it stores multiple versions of DLLs and backup files for Windows Updates. On a long-running Server 2008 R2 instance, this folder can easily consume 10GB–20GB of precious SSD or SAN storage.

Step 1: Install Disk Cleanup (Without a Reboot)

In Server 2008 R2, the Disk Cleanup utility is technically part of the “Desktop Experience” feature. Usually, installing this requires a reboot—something most admins want to avoid.

Instead, you can install the standalone update package (KB2852386) that specifically adds Disk Cleanup functionality:

For x64 Systems: Download KB2852386 for Windows Server 2008 R2

Step 2: Launching the Cleanup Wizard

Once the update is installed, you won’t find it in the Start Menu immediately. You can launch it via the command line:

Open Run (Win + R).
Type cleanmgr and hit Enter.
Select your C: Drive.

Step 3: Cleaning System Files (The “WinSxS” Secret)

To actually shrink the WinSxS folder, you must target the Windows Update files.

When the wizard opens, click the Clean up system files button (this requires Administrator privileges).
The tool will scan again. Look for the new option: Windows Update Cleanup.
Check this box along with any other items you want to remove (Service Pack Backup files, etc.).
Click OK.

Step 4: Finalizing the Shrink

Unlike standard file deletion, the WinSxS cleanup happens during the next reboot.

When you restart the server, you will see a message: “Configuring Windows updates, X% complete. Do not turn off your computer.” * Do not interrupt this process. This is the system physically removing the redundant files from the WinSxS directory.