I was not aware that it's possible to install straight *.pm files with ppm. Normally you'd use ppm to install modules that have been specifically packaged to use that installer.

However, in this case, you could just put that URL you cite in a browser which will allow you to download the latest ExtDBH.pm module to your hard drive. Just save it to the path where Perl can find it, such as c:\perl\site\lib and you should be okay.

That said, unless you really need this module, I wouldn't bother. It's a thin abstraction over DBI which doesn't add much. It's only marginally more convenient than straight DBI, in my opinion.