Sometimes the Quick Connect Service Account creates a large number of *bfb files and can overload hard drives? Are they safe to delete? These files are located at %Users%\%ServiceAccount%\AppData\Roaming\Microsoft\Crypto\RSA\SID\*
Microsoft Operating Systems create a cryptographic key in the AppData\Roaming\Microsoft\Crypto location and store them indefinitely when making connections that require RSA Encryption Keys.
If there are too many files in ..\AppData\Roaming\Microsoft\Crypto, delete them manually. This is rarely an issue and does not cause any harm other then consumption of disk space.