Start by right-clicking on the desktop icon and choosing Properties.
Click on the Shortcut tab, and look in the Target window.
You will see listed the .exe file that starts the program, as well as the folder that contains it. Note the name of the .exe file, then delete the folder, even if it is the same one you have been deleting all along.
Next, open Windows Explorer and look through its menus for the Folder Options choice. Click that, and in the View section, choose the one that will make Windows Explorer show all files, including System files.
Now, using Windows' Search or Find utility, look for other instances of the porn program's .exe file, using a truncated form of the file name as a search term.
For example, if the .exe's file name is oohbigboy.exe, you might search for "oohbig*.exe" without the quotes. That asterisk is known as a wild card. Because it is present, the Search or Find utility will look for variations of oohbigboy.exe that begin with "oohbig."
I suspect, though, that you will have to look through the Windows Registry for references to the porn program and delete those as well.
A tutorial for dealing with the Registry follows.
Q: You often recommend editing the Registry to remove references to programs or devices. How does one do that?
A: Start by calling up the Registry Editor. To do so, go to Start/Run, then type "regedit" without the quotes in the Open box. Click on OK.
Once in the Registry Editor, make sure that the topmost entry - My Computer - in the left-hand pane is highlighted.
Go to the Edit menu and click on Find. In the window that opens, see to it that the boxes to the left of Keys, Values and Data are all checked.
In the "Find what" box in the same window, enter the name of the program or device you want to find and purge, then click on the Find button.
When an entry is found and displayed in the editor's right-hand pane, put your cursor on the specific item you want to delete. Right-click on the entry, and from the pop-up menu, choose Delete.
Return to Edit, choose Find Next, and delete the next reference.
Repeat the process until no more references to your search term are found.
One reason the Registry is so complicated is that there can be multiple references to any program, peripheral or device. So, you will have to do additional searches, this time looking for other references to the program or device.
You do so by looking for the manufacturer's or publisher's name or with synonyms for the product itself. For example, if you want to remove references to Microsoft's IntelliMouse, you would search for IntelliMouse. Then you would conduct a second search using Microsoft as a search term.
Even a search using "mouse," without the quotes, might be in order.