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.
