running as a service or application? If service , start it as n application and see if messages display on the pvx windows. Make sure you do not hide the tasks in webengine.. Usually the error message is indicating that the web engine is not running.
Sage's Manual list the following for it:
Unable to establish a connection
The Web Engine has stalled or is not running. If you are running the
Web Engine as a service, you can verify whether it has stalled or
stopped. Open a Web browser and type
http://127.0.0.1:PORT/IW_Login.m4p;login (where PORT is the
port at which the Web Engine is running). If you get a Business to
Business logon prompt, then the Web Engine is running. Stop and
restart the service. If the Web Engine still does not start, then contact
Sage for further assistance.
The Web Engine port number in the MASISAPI.ini file is incorrect or
missing. Open the MASISAPI.ini file in Notepad, and verify that the
port number in the file matches the port number displayed on the
Web Engine Configuration window and eBusiness Manager Setup
Options.
The Web Engine port is blocked. A router and/or firewall may be the
cause.
I have seen it happen with a user who had a very large catalog that each time a user would search it would crash the session. We had to move the webengine to the same server as the MAS90 folder to fix. Might also check the web activity log.