Apart from the new Modern UI look and tablet-optimized features, Windows 8 also comes with new network, personalization, system administration and security related options. Like previous versions of Windows, it enforces strict file access and system component usage restrictions to prevent users from tweaking the default system management, administration and security parameters. Almost all the Special Folders, including user profile folders, system32, library folders etc, have been assigned special permissions by System, and this virtual user allows them to create and read file listings, manipulate extended file attributes, delete folders and sub-folders, and remove junk files from the folders. The Explorer is one such User Profile-related special folder, which can delete thumbnail database as soon as its size reaches a certain limit. If you’re among those who deal with massive photo collections and want to restrict File Explorer folder from deleting your thumbnail database files, here’s is how you can do it in Windows 8.
In what follows, we will guide you through the process of changing special permission assigned to Explorer folder. When you deny the delete permission for Explorer folder, you can keep the thumbnail database files as long as you want to. However, it’s worth mentioning here that you will not be able to delete the thumbnail files, and in order to clean the Explorer folder from junk data, you need to allow special permission to Explorer folder.
First off, make sure that you’ve logged in to Windows from Administrator account or have required administrative rights to change the SYSTEM user’s special permissions. To begin, use Win+R hotkey combination to open Windows Run console, type in %userprofile% and press enter. Now, navigate to \AppData\Local\Microsoft\Windows folder, and then right-click Explorer folder to bring up its Properties sheet.
Since you want to change the file access permissions, head over to Security tab, and click Advanced button, present underneath the Permissions table.
This will open the Advanced Security Settings for Explorer. Unlike previous Windows versions, Windows 8 doesn’t allow you to edit the SYSTEM principal (virtual user) file permissions, but you can add a new principal and choose to inherit its permission to other principals in the list. In order to add a new principal and set its file access permissions, click Add.
It will open Permission Entry for Explorer dialog box. Now, hit Select a principal link.
In Select User or Group window, you can either manually add System object by typing in system followed by clicking Check Names button. Once added, click OK.
This will add SYSTEM principal. Now, select Deny and This folder, subfolders and files from Type and Applies to drop-down menus, respectively. Hit Show Advanced permissions link to view both basic and advanced permissions. Now, enable Delete subfolders and files and Delete options and hit OK button to deny the said file permissions for Explorer folder.
Upon click, it will add a new permission entry. Now, click Apply to set new permissions for System folder, and before you close the Advance Security Settings window, navigate to Effective Access tab to confirm the newly applied permissions.
In Effective Access tab. select the user whose file access permissions you want to verify. Click Select a user, type in SYSTEM in Select User or Group window, and then click OK. Once the system user is selected, click View effective access button to check whether the Delete and Delete subfolders and files permissions are limited or not.
In case, it doesn’t restrict the delete permissions, log off from Windows and log in as administrator, and then follow the above mentioned steps. When the delete permissions from Explorer folder are revoked, it will stop deleting your image thumbnail database files. Please note that Windows Disk Cleanup utility will not be able to delete the thumbnail cache, and unless you reinstate Explorer folder’s Full Control, you have to manage the thumbnail cache files by yourself.