nixed: I've made some suggestions on your error 200 problem at the end
I think my own FH problem is now solved thanks to clues posted here - So thanks guys
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Unlike you, I wanted to abandon all old backup data and restart from scratch, but FH kept failing to initiate (post #20)
After reading Steve C's posts #16 & #18 carefully, FH now seems to be OK for me.
I went a bit further than Steve recommended
I deleted both of the 2 subfolders (Configuration and Data) from %LocalAppData%\Microsoft\Windows\FileHistory
- Stopped FH in Control Panel
- Checked FHSVC was actually stopped (Task Mgr/Services)
- Deleted both Configuration and Data from %localAppData%\Microsoft\Windows\FileHistory
leaving FileHistory empty - I also cleared the File History event log, just to give me a clean sheet
- Re-booted while FH was switched OFF
After restart, I also deleted FileHistory folder from my external backup drive
(You probably won't want to do this )
In Control Panel, I turned FH back on. I think I had to click Run Now to kick it off. and all was well!!

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nixed Here are my guesses at solving your problem
Looking first in the backup drive, the Data folder contains all the actual file backups
and the Configuration folder is small holding Config1 & 2 and Catalog1 and 2
The %LOCALAPPDATA% Configuration folder holds Config1 & 2, Catalog.EDB 1 & 2 and Catalog.JFM1 & 2
- similar to but not direct copies of the Backup equivalent.
I think the local Data folder (called the staging area) must be the local data cache for when the backup drive is offline
Guess 1
The local Data staging area folder is not critical and is created at run time
Guess 2
Your error 200 may be caused by incompatibility between the two sets of Config and Catalog files
I guess the versions on the backup drive are the more important
If you delete the APPDATA versions first, there can't be a conflict.
- but the backup versions could be corrupted somehow.
Conclusion.
You've got nothing to lose.
Do steps 1 to 3 and 5 as I did above (maybe not step 4)
Explore the top folders in your backup drive, just so you know what they look like
e.g. note folder names & paths to the Config files
OR, if you want to, Delete the backup FileHistory folder (Nuclear option)
Then restart FH. If it finds existing backup data, accept and continue.
If FH restarts successfully, I suggest you again explore the backup folders as above and update your record
Good luck