Hi Giacomo,

By chance, are these older Cisco IOS devices or something else entirely?  I've seen that sort of error with old IOS devices where the device hit a bug where a save was done but was not successful (and reboot would be needed).  

You may want to look at the device's log and see if you don't see the issue and with that, you might be able to search the device vendor's support page.  

Other thing you could try, when the task completes, maybe wait some time, re-run the task and enable session logging and when that task finishes, look in there to see if there's more information than what you have seen so far.  

Lastly, while I've not seen a case where NA would cause a problem like that, it might be some scenario I've not done, but I'd say check and see if there's not a newer Device Driver Pack available, newer version of NA (or patch released for your current version) and you should find some note on what was addressed - might be that this was something addressed.  

Hope this helps,

Chris

Hi Chris,

thanks a lot!

we rebooted the device and take snapshot worked again.

Thanks,

Giacomo