Q. When do the file hashes first get created for my BranchCache-enabled file share?

A. Normally, the hash on a file that's hosted on a BranchCache-enabled share is generated the first time a user requests the file. This means that the first user to request the file won't actually receive the hash, because it's being generated as the data is sent. The second user to get the file will be sent the hash values, and therefore the data will be cached by BranchCache. If you want the first user to cache the file, you can run the hashgen command on the file share content periodically, which will create the hashes on specified files in advance.