I found this useful discussion from Google;
http://gadgetopia.com/post/3837
It's long, (you need to read the two other pages linked at the bottom), but you may find some tips and tricks there.
What I didn't see there, (surprisingly), is any reference to either disabling the Startup file or disabling the Service. Possibly there are no such options, but you can check that.
Open the System Configuration Editor by going to Start > Run, type in msconfig and click OK. In the editor goto the Startup tab and look to see if the Installshield is set to load at startup. If so, you can deselect the option there.
If it is a Service, goto Start > Run, type in services.msc and click OK. See if there is a listing for Installshield and if so, double click the entry to display the Properties window. Here you can change the "Startup type:" to Disabled if you wish.
Before doing either I would create a System Restore point first, in case anything breaks.
Mark
I recently purchased a Dell Inspiron 530 Intel(R)Core(TM)2 Duo CPU E4500 @2.20 GHz - 1.18 GHz, 1.99 GB of RAM. I have the Installshield Update Manager installed, and am having problems with it as it relates to certain NET. updates, and also with Adobe Flash downloads and installation. My question is this - can I safely remove Installshield, and rely soley on the Microsoft/Windows update sites to handle my program updates and installations? If this is not a vital piece of software, I'd rather not have it. There are too many 'workarounds' with the applications I'd like to use, and I very nearly had to wipe my hard drive clean because I'm not proficient enough to understand what I'm doing and what my actions are affecting. I want to make sure that if I can uninstall this software and that all traces of it are completely delected from my pc - with nothing 'hidden' that may crop up later to cause me problems. Thanks for any and all help!

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