QlikSense: ErrorCode.-128: "Internal engine error"

[JustinDallas]

Hello Everyone,

I have a QlikSense installation which has the version of Qliks Sense 3.1 SR1, serversuite:10.3.6. When I go to the QMC, I see that my account has "RootAdmin" set.  However, when I click on a document, I get nothing but a bunch of circles.  Using the Dev Console, I see that the engine.js response looks like this with an error code of -128.,

When I go to search for "logs" under C:\ProgramData\Qlik\Sense, I don't get any results back.  Does anyone know why the system may be outputting this error?

Any help is greatly appreciated.

[JustinDallas · Accepted solution]

We restarted the QlikSense server and the error went away.

[florin-vasile]

How to mark a restart as a solution?

Before doing a restart... How can I found the reason? 

Is there any location where I can see a log file to find the reason?

Thanks.