Cannot Read directory error repeats indefinitely

[wus]

I am using FreeFileSync to keep files on my main PC in sync with those on a directory on my NAS, which is mounted as a network drive under Windows. Basically, this works, but recently I get more and more error messages like the one in the following screenshot. It doesn't happen every day, but if it does, it just doesn't run through.

Screenshot 2022-03-08 10.32.22.png (16.54 KiB) Viewed 665 times

I tried to open this directory on the NAS using the Windows explorer. This was possible without any problem.

So I clicked "Retry". But FFS gave me the same error message again, almost instantly. But it listed a different directory that it couldn't open.

Question 1: Do you agree that the fact that it did not list the same directly once more as "could not open" means, that it could read it after I clicked "Retry"? Why couldn't it read it the on the first try then???

I kept clicking "Retry" many times (when I first examined this error), but FFS kept listing directories it "could not read". It seems that once it ran into this issue, it can't get out of it. I also clicked "Ignore" and "Ignore all" on other instances, but it always kept showing new error messages and eventually stopped.

Screenshot 2022-03-08 10.37.46.png (69.68 KiB) Viewed 665 times

I verified that all the directories shown in the screenshot above could be read without issues by the Windows explorer.

Question 2: How can I get FFS back to work without these issues?

[xCSxXenon]

Obviously do the basic troubleshooting, restart PC/NAS, disconnect and remap the location.
I have seen this caused by an intermittent network connection. If my case, there was a bad ethernet cable connection that was causing dropouts

[wus]

Intermittent network connection certainly isn't my problem. I have checked it over and over again, over the past few weeks - last time yesterday, before I posted here.

What do you mean with "disconnect and remap the location"?

My NAS is set up to shut down every night and restart in the morning. Typically, I also shut down my main PC overnight. When I restart it in the morning and leave the PC idling for 10 minutes or so, FFS runs through without problem.

But is not enough that FFS works well after restarting both devices.

When I go away from the PC during the day, I typically set it to energy saving mode. And after reactiving it later, the described problems often occur.

How can I go about this?

[Zenju]

Question 1: Do you agree that the fact that it did not list the same directly once more as "could not open" means, that it could read it after I clicked "Retry"? Why couldn't it read it the on the first try then???

I kept clicking "Retry" many times (when I first examined this error), but FFS kept listing directories it "could not read". It seems that once it ran into this issue, it can't get out of it. I also clicked "Ignore" and "Ignore all" on other instances, but it always kept showing new error messages and eventually stopped.

It seems you're using parallel file operations. Then there was a temporary network drop, and all parallel operations failed at the same time. But only one of them is reported at a time. So when you click retry to dismiss the first error message, the next error in queue comes up, even though at the time you're clicking, the temporary network issue is probably already gone.

Solution: use automatic retry (maybe retry once with a few seconds delay).

[wus]

I will try what you recommend. Thank you!

However, IMHO,

at the time you're clicking, the temporary network issue is probably already gone

is clearly a bug: It does not retry then. Obviously, when there are several fails in the queue and I click Retry, it should retry all of them.

[Zenju]

These are unrelated errors as far as FFS is concerned. "retry" shouldn't consider errors that weren't shown beforehand. Solutions?

• Maybe aggregate all errors "at a time" (what does that mean? which interval) and show one huge error message. What if the user wants to retry one error, but ignore another. Lots of problems...

• Somehow only aggreate errors "of the same type"? How to do this in general?