I'm guessing you installed without sufficient rights to change the registry. Try getting Power User or Administrator rights and reinstalling. The behaviour you describes strongly suggests and incomplete install to me. After installation you should be able to do assoc on .pl files and get a binding to Perl, which itself should be bound to the perl interpreter.

E:\perl562-21256\perl\win32>(assoc .pl) && (ftype Perl)
.pl=Perl
Perl="E:\Perl\bin\perl.exe" "%1" %*
[download]

You can try using the same two commands to fix things up, but Perl should have done this for you.

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demerphq

First they ignore you, then they laugh at you, then they fight you, then you win.
-- Gandhi