When I try to delete a thumbs.db file under Win7 on a network drive it fails because the file is opened by Win Explorer.

Hey NeilHMurphy,

thumbs.db file is a thumbnail cache.The thumbnail cache thumbs_*.db database files are stored at the hidden system folder below:

C:\Users\User-Name\AppData\Local\Microsoft\Windows\Explorer

You can clear the thumbnail cache via Disk cleanup utility.

1. Open Disk Cleanup by clicking the Start button. In the search box, type Disk Cleanup, and then, in the list of results, click Disk Cleanup.

2. In the Drives list, click the hard disk drive that you want to clean up, and then click OK.

3. In the Disk Cleanup dialog box, on the Disk Cleanup tab, select the check boxes for the file types that you want to delete, and then click OK.

4. In the message that appears, place a checkmark on Thumbnails. Click on OK.

5. When it prompts you if you don’t to permanently delete these files, click on “Delete Files”.

6. Wait till the utility completes the process.

This deletes all the thumbs.db files from the computer. Verify the same.

Details on Disk cleanup utility:

Delete files using Disk Cleanup**http://windows.microsoft.com/en-us/windows7/Delete-files-using-Disk-Cleanup**

In case you want to turn off caching of thumbnails, there are couple of ways to do so. One includes editing the registry and the other includes using the Local Group Policy Editor.

Method 1: Turn off caching of thumbnails via Group Policy Editor.

In case Local Group Policy Editor is available on your edition of Windows 7, you can turn the feature off from there.

1) To start the Local Group Policy Editor, click the Windows 7 start icon and type gpedit.msc in the search text box and hit Enter.

2) The Editor will open to the top-level Local Computer Policy, so you will have to expand the User Configuration item in the left-side pane of the Editor window.

3) Drill down through Administrative Templates, then Windows Components, and click on the Windows Explorer item.

4) Near the top of the list in the right-hand pane of the Editor window you will find the setting “Turn off the caching of thumbnails in hidden thumbs.db files”

5) To edit this policy setting, either double-click on the title of the policy or click the link titled “Edit Policy Setting” to the left of the setting list after you select the policy.

6) To change the policy, merely check the “Enabled” radio button and click OK.

Close the Local Group Policy Editor and you will notice that all of those thumbs.db files have disappeared.

Method 2: Turn off caching of thumbnails via Registry Editor.

Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article below:

Back up the registry**http://windows.microsoft.com/en-US/windows7/Back-up-the-registry**

   1. Open the Registry Editor by typing regedit.exe in the start search field.

   2. Navigate to the following registry branch:

*HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced*

   3. On the right pane, double click on DisableThumbnailCache value, and set its value data as 1. If the registry key of DisableThumbnailCache does not exist, create a new DWORD value with that name. Set the value as 1.

   4. Exit Registry Editor.

   5. Logoff and login again, or restart the computer for the changes to take effect.

Regards,

Shinmila H - Microsoft Support

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