COMPARE session: "sync.ffs_lock" file not found to delete - cannot continue

[Kyryhniann]

Greetings all. I am hoping someone can help me with this seemingly unique problem.

I have already read similar posts here in the forums regarding this error message and what it means, but I am unable to find ANY "sync.ffs_lock" files in the root directory of EITHER folder (left or right side). It just doesn't exist, else I might have been able to delete it/them as others have suggested.

Here's what I did to GET the error:

• Open FreeFileSync (FFS) 13.8 as Administrator
• At the top of the LEFT panel, added the Music folder on my external HDD
• At the top of the RIGHT panel, added the Music folder on my OnePlus 8 Pro cell phone
• Clicked the "Compare" button at the top

• Cancelled the "Waiting while directory is in use..." error message
• Closed FFS
• Opened Task Manager to see if any other instances of FFS were running so I could End Task them, but there were none.

• Re-opened FFS as Admin - the previous folders selection was still there
• Clicked the "Compare" button at the top
• SAME error with the "Waiting while directory is in use: "...\Music\sync.ffs_lock"

OTHER directories seem to work fine without the error. I HAD actually used these 2 directories as my very first comparison and it DID work fine. But after that, nothing, because of the error which won't go away.

I have no idea what's causing this or how to fix it, and am not sure if it's because 1) I'm using a cell phone folder to compare (in "Transferring files via USB mode) or not.

Any help would be much appreciated so please let me know and thanks in advance!

[xCSxXenon]

FFS can detect stale lock files, so it might work if you wait 30-60 seconds. Otherwise, you may have to enable visibility of hidden files to see the lock files in order to delete them

[Kyryhniann]

Thanks so much for the reply. On two separate occasions I waited 15 minutes. I always have Show Hidden Files enabled, so that's not it either.

I appreciate your reply. Might you have any other suggestions?

[Plerry]

Not preferred, but you can prevent the use of *.ffs_lock files by setting the LockDirectoriesDuringSync flag in your GolbalSettings.xml file to false.
Make sure to read the risk/disadvantage of setting that flag to false, and if that is relevant for your use.