"No Connection" in AJAX

[Anonymous]

Here is a problem.
A client is getting randomly "no connection" error while using AJAX.  It may happen twice a day or once in a few weeks.  As long as one user gets the error, same problem affects all users, that means that the problem is on the QVS side.  It doesn't look as a performance problem, RAM and CPU usage are not hitting any high values.  Restarting QlikView Server service fixes the problem, that is until next time.

Notes:
- In Events log:  Error   Session Recovery Failed: An exception (C) occured during create $LASTKNOWNSTATE on document ...

- in Sessions:    Server shutting down
- It never happens with IE Plugin
- Working Set settings are 70/80.
- QlikView Server service is restarted nightly.
- Version is 11.20 SR5

What can be wrong?  How to fix it?

Thank you,
Michael

[ergustafsson · Accepted solution]

Hi Michael,

The quick fix is to turn off Session Recovery (QMC > QVS Settings > Documents), then this should not happen. However that is not solving the root cause which might be .shared files or any kind of customization.

I recommend you to open a support case to make a thorough investigation.

Regards,

Erik

[Anonymous]

Thanks Eric,

In fact, I did open a support case in parallel with this question.  They made the same recommendation, plus another one, which is probably not relevant to this problem but certainly useful.  The client was going to turn off Session Recovery yesterday night, and it will take a few days to tell if it helps.

Regards,

Michael

[Anonymous]

Three days, no errors...

Changed from "helpful" to "correct"