Error: Class not registered.
The line number was pointing to the line with the window.open code. We tried uninstalling and reinstalling Internet Explorer but to no avail.
After some searching we came upon this thread in a forum with the solution to the Class not registered error.
The solution was simple just re-register the IE dlls using the following commands in a batch file. You could also copy and paste directly into a command prompt to get the same result.