Dialog System dsrx-nt error

Hello.

One of our customers reported an error related to NetExpress 3.0.14 Dialog System. This error is a cblrtss.dll exception that appears in the MFDEBUG.LOG file. In this file, the call stack shows: our application --> DSRUN --> dsgrun --> dsrx-nt. There is no more information.

I searched the dsrx-nt file and only found it into DSGRUN.DLL.

Can you tell me what is dsrx-nt and which can be the cause of that error?

Thanks beforehand.