A customer had a server-side Web application which creates a large number of image files. The customer was concerned that the system would spend a lot of effort generating thumbnails to be put into the thumbs.db file and wanted to disable the thumbs.db file in order to improve the performance of their Web application. The customer liaison added, “From a brief experiment, it seems that the thumbs.db file is written when a user displays thumbnails on Explorer. Merely creating and copying image files does not trigger the creation of a thumbs.db file. I don’t think the customer needs to worry about the overhead of the thumbs.db file since neither the user account of the Web application nor the SYSTEM account will create a thumbnail cache. Is that correct?”

Yes, that’s correct.

The thumbs.db file is created by Explorer or any other application that uses Explorer’s thumbnail cache. It is unlikely that the customer’s Web server is using the Explorer thumbnail cache, so the file won’t be created.

To be extra sure, the customer can set the policy User Configuration, Administrative Templates, Windows Components, File Explorer, Turn off the caching of thumbnails in hidden thumbs.db files.

The customer liaison thanked us for confirming what their experimentation revealed.