InstallShield Update Manager – ISUSPM.EXE
Isuspm.exe is the InstallShield Update Manager. InstallShield is a very popular program installer. Chances are good that you have lots of programs on your system that used that as the program installer.
Isuspm.exe can be used to check for updates or additional product information. When an update is available it is listed in the Update Manager. This link, when clicked, will take you to the download and any release notes or other product information for that update. You may also have a file called agent.exe on your system. This file the Update Agent and is needed to automatically download the product updates.
If you like this update capability, then leave both of these files in place. If you don't care for it, then we'd recommend removing both files using WinPatrol or uninstalling via Control Panel > Add/Remove Programs. Depending upon when you installed the software, it may be listed as "InstallShield Update Manager" or "FlexNet Connect" or "FlexNet Publisher". The program was renamed after Macrovision bought InstallShield.
You'll find additional information about these files at http://www.macrovision.com/products/flexnet_publisher/flexnet_connect/index.shtml and at http://www.macrovision.com/products/flexnet_publisher/flexnet_connect/resources/faq.shtml#FAQ100326.