Background
There are numerous backup solutions out there for Windows and they come in many different forms. From a file copy and/or syncing tool like SyncBackSE to whole hard drive backup utilities based on Volume Shadow Copy like Acronis TrueImage or Norton Ghost to block level copy tools like dd. Each of these solutions offers different pros and cons versus the "Windows Backup and Restore Center" feature built-in to Windows Vista and Windows 7. I am not interested in discussing alternative backup solutions here however, as that has already been covered by numerous other questions.
Constraints
There are two "types" of backup supported by the "Windows Backup and Restore Center"(WBRC):
- File backup (which Windows calls "Back Up Files")
- Full System Backup (which Windows calls "Complete PC Backup)
I am interested in a solution which supports either and/or both types of backup with WBRC.
Questions
- How can you use a TrueCrypt encrypted mount point as the destination for the built-in "Windows Backup and Restore Center" feature in Windows Vista and 7?
Best Answer
Background
The reason you can't select the TrueCrypt mounted volume as a backup destination for the built-in "Windows Backup and Restore Center" on Windows Vista and Windows 7 is because your user account mounted the TrueCrypt volume but the Backup Service runs as the SYSTEM account. 2
Contraints
Gotchas
If you also use TrueCrypt to encrypt your backup source, there is a limitation on TrueCrypt (at the time of writing, Version <= 6.3a) on support for the Volume Shadow Copy service:
Since the File Backup (aka "Back Up Files") option uses the Volume Shadow copy Service (VSS) to perform its backup, this means you will not be able to backup sources that are encrypted outside of the scope of the system encryption key (e.g. an external hard drive that has been encrypted or the contents of a file based TrueCrypt volume).
The folder share will not survive being unmounted and mounted to a different drive letter. (It may not even survive unmounting and remounting to the Same drive letter, but I haven't confirmed this yet). If you don't want to have to manually create this share each time, you may need to script out it's creation as a log-on script or something.
Solution
NOTE: The following instructions are for Windows Vista Business 64-bit SP2 but the steps should be the same on any supported Vista editions and very similar for any supported Windows 7 editions. See above for supported editions.
To perform a File Backup (aka "Back Up Files"):
\\COMPUTERNAME\ShareName\ (e.g. \\JOHNS-COMPUTER\Backup\)
NOTE: The Complete PC Backup on Vista doesn't give you the option to backup to a network location in the GUI, but you can do so from the command line using WBADMIN.EXE on supported editions.
To perform a Full System Backup (aka "Complete PC Backup"):
WBADMIN START BACKUP -backupTarget:\\COMPUTERNAME\ShareName -include:C: -user:<youruser> -vssFull (e.g. WBADMIN START BACKUP -backupTarget:\\JOHNS-COMPUTER\Backup -include:C: -user:jdoe -vssFull )
References