Unable to sync due to illegal state exception

Issue:

You encounter issues/problem with filesync or syncing data back to dfs which might manifest as a hash mismatch

Root Cause:

Filesync expects the file object to be in a certain state, having a specific distinct sha1 hash, due to some unknown reason the sha1 hash of the modified file isn't registered with filesync and causes a hash mismatch exception

Resolution:

The only viable solution would be to calculate the sha1 checksum of all the files on dfs and compare those with the hash in the run logs.

Basically identify the illegal hash from the logs and execute a simple find command to locate the problematic file : 
find . -type f -exec sha1sum {} +
Remove this problematic file from dfs once found.