Uninstalling Trend Micro Client/Server Security Agent without using Password

Method 1:

To uninstall the Client/Server Security Agent, do the following:

On the target machine, close all browser applications.
Open a command prompt window.
For 32-bit OS: Go to C:\Program Files (x86)\Trend Micro\Security Agent\ directory. For 64-bit OS: Go to C:\Program Files (x86)\Trend Micro\Security Agent\ directory.
Type the following command: ntrmv -980223

Method 2:

Trend Micro has also supplied a registry edit that can be found at this link. Manually uninstalling the Client/Server Security Agent.

Open the Registry Editor. Note that you should always create a backup before modifying the registry as incorrect registry changes may cause serious issues.
Do one of the following:
For a 32-bit operating system, go to the HKEY_LOCAL_MACHINE\SOFTWARE\TrendMicro\PC-cillinNTCorp\CurrentVersion\Misc registry hive.
For a 64-bit operating system, go to the HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\TrendMicro\PC-cillinNTCorp\CurrentVersion\Misc registry hive.
Look for the registry DWORD "Allow Uninstall".
If this is present, edit the DWORD and change the value from 0 to 1.
If this is not present, create the string as follows.
Right click the Misc. folder and select New > DWORD value.
Create the registry name Allow Uninstall.
Double click the new entry and change the value from 0 to 1.
Click OK.
You should now be able to uninstall the program without getting any prompt for a password.