Since this morning getting "Microsoft JScript runtime error.", never encountered before!

Hi Dave,

Have you tried to execute this loop step-by-step under debugger in TestComplete and check whether the problem persists?

My current understanding is that:

-- There was IE browser running in the system;

-- The loop found it on the first pass and proceeded to .Close() statement;

-- The browser was commanded to close and TestComplete waited for 0.5 sec for the browser process to end;

-- 0.5 sec was not enough for the browser to close thus the second loop pass still found the process and proceeded to .Close() statement;

-- By the moment of actual execution of the .Close() method IE process has ended. This invalidated the reference to the browser process and caused the error.

As a quick fix attempt try to increase the parameter of the .Close() method from 500 to, say, 2500 and check if it helps.