Encrypting hard disk

Hallo!

A question:

I would like to encrypt the data I have on an external hard drive in such a way that
I can take it away from my normal desktop PC and just plug it in to other PCs when
travelling. Can this be done with Comodo Encryption software or do you have to have
the program installed on all PCs where you want to attach the hard drive?

If it does not work with Comodo - any suggestions on how I can make it work?

Today I use WinZip and encrypt all files as a mega Winzip file but that is not optimal
and even if the encryption is strong you can still read all the file names…

Jon