2016 Web Client error message (The network is currently unavailable...) when running a report

apap

Hi everyone,
we are getting this error message: "The network is currently unavailable. The connection will resume when network access is restored" when running reports from a 2016 Web Client even after some time the report is finishing correctly and populates correct the dataset and the layout. . The Web Client is running on the internet accessing a public web base url.
Because we haven't seen it again, does anybody know from where this message is populated?
Any helpwill be appreciated.
I will update later again the post because right now we are investigating the event viewer of the servers and the logs of the IIS
Kind regards

RockWithNAV

Try Re-login, seems some sort of connection issue with NAV or may be with internet.
Earlier you were able to login??