If you have found a Web page with an advert that you want to remove, use the following steps:
First of all, go the Filters tab of the properties dialog. There you will see a list of filters, with options to add new ones, delete old ones and save them to disk. They are automatically stored in a file pointed to by the registry - the Save and Merge options are for moving them to other computers, and for backing them up.
Find the URL of the offending advert (note: this is not the URL that the advert links to, but of the actual graphics file itself). To do this on Netscape, right click on the advert and select Copy Image Location to put it on the clipboard. On Internet Explorer, right click on the image, and select Properties, then copy the Address (URL). On Opera, right click on the image, and select Copy Image Address. On other browsers, if you can't find a similar way of getting the information these other methods might help.
In WebMask, create a new filter. Paste (Ctrl+V) the information into the Host edit box at the bottom of the filters page. The URL will automatically be broken up into the host and the path.
Check the host looks correct - the hostname e.g. www.lagach.com, should be in the Host box.
You might want to use a Partial filter or an Exact filter. The default is partial.
Now, click on Apply to accept your changes.
Go back to the browser, and select refresh. The advert should have disappeared.