computer help .dll files

[doubleup]

My zonealarm pro firewall has ceased to function correctly.  It says that there is a problem with a couple of .dll files.  If I change the date on my system (go back to 15/07) it loads correctly and works even when I correct the date, so I assume that there is a date on the .dll files.  Can I edit these files?  What prog can I use to edit if possible?

[StuartHopkin]

there pretty basic paremeter files, you can probs open them in notepad but be careful!