Recently I’ve been having issues on a few workstations where the Trend Micro OfficeScan installation became corrupt. Attempting to re-install OfficeScan again would result in an error message saying it was already installed. All the tools that Trend Micro provided wouldn’t remove the remnants. Trend does offer a manual uninstallation method (http://esupport.trendmicro.com/solution/en-us/1039283.aspx), but takes too much time to perform on multiple workstations.
I created a VBScript that automates the manual uninstallation instructions. For a small portion of the code it depends on Microsoft’s DevCon utility (http://support.microsoft.com/kb/311272) and won’t run without it. Please extract the DevCon utility to C:\Windows\System32.
Automated Manual UnInstall Trend Micro OfficeScan – https://www.brandonclaps.com/downloads/OfficeScan_Remove.zip
Hope you find this useful.