======Temporary Files======
This is for files in the VPOP3\_temp folder

Most of the filename is the hexadecimal timestamp (in Windows 'FILETIME'/65536 form) with a 4 digit hex sequential number afterwards. The first letter or two (usually G-Z) can tell something about what caused the file.

====VPOP3 8.0-8.7====
  * G*.DAT - web UI temporary file
  * H*.DAT - held outqueue message before import to DB
  * Q*.DAT - outqueue message before import to DB
  * MS*.DAT - message files which have arrived and are waiting to be delivered into a user's mailbox
  * T*.DAT - miscellaneous temporary files
  * BAD*.DAT - message files which failed to be delivered. The VPOP3 administrator should be notified when one of these files is created. It can be converted to an *.EML file and opened in many email client applications
  * OP*.DAT - outmail preprocessing queue  (legacy extension)
  * XP*.DAT - outmail preprocessing work file (legacy extension)
  * PQ-*.DAT - outmail processing work file (legacy extension)

====VPOP3 8.8+====
  * C*.DAT - web UI temporary file
  * H*.DAT - held outqueue message before import to DB
  * Q*.DAT - outqueue message before import to DB
  * MS*.DAT - message files which have arrived and are waiting to be delivered into a user's mailbox
  * BAD*.DAT - message files which failed to be delivered. The VPOP3 administrator should be notified when one of these files is created. It can be converted to an *.EML file and opened in many email client applications
  * T*.DAT - various temporary files
    * TG*.DAT - work file for message dequeing 
    * TH*.DAT - message for Spamfilter Bayes Analysis via web administration console
    * TI*.DAT - certificate file for certificate validation via web administration console
    * TJ*.DAT - work file for message archiving
    * TK*.DAT - work file for message archiving status message
    * TL*.DAT - work file for custom message archiving searches
    * TM*.DAT - work file for custom message archiving
    * TN*.DAT - work file for message archiving extract to ZIP
    * TO*.DAT - work file for attachment processing rewriting
    * TP*.DAT - work file for attachment processing rewriting
    * TQ*.DAT - work file for mailing list digest processing
    * TR*.DAT - work file for custom file transfer processing
    * TS*.DAT - temporary file for IMAP4 APPEND command
    * TT*.DAT - upload work file for Web UI
    * TU*.DAT - work file for custom message archiving retrieval
    * TVH*.DAT - work file for message processing - add header
    * TVI*.DAT - work file for web message sender sent items
    * TVJ*.DAT - work file for bayes analysis REST
    * TVK*.DAT - work file for message restorer
    * TVL*.DAT - work file for outqueue REST
    * TVM*.DAT - work file for message distribution - modify headers
    * TVN*.DAT - work file for LAN Fwd message preprocessing
    * TVO*.DAT - work file for outgoing message preprocessing
    * TVP*.DAT - work file for local folder message preprocessing
    * TWH*.DAT - work file for S3 backup upload preprocessing
    * TWI*.DAT - work file for S3 backup upload encryption
    * TWJ*.DAT - temporary file for S3 restore
    * TWK*.DAT - work file for S3 restore
    * TWL*.DAT - work file for S3 restore decompression
    * TWM*.DAT - work file for S3 restore decryption after decompression
    * TWN*.DAT - work file for S3 restore decryption without decompression
    * TXH*.DAT - temporary file for SMTP service
    * TXI*.DAT - work file for internal signatures
    * TXJ*.DAT - work file for outgoing signatures
    * TYH*.DAT - temporary file for live updates
    * TYI*.DAT - work file for mailing list archives
    * TYJ*.DAT - work file for mailing list moderation
    * TYK*.DAT - temporary file for Webmail Sent Items processing
    * TZ*.DAT - temporary file for Lua scripts