Well, am new here, so I really hope I am in the correct forum.

My question is both simple and confusing at the same time, but please humor me. It goes like this:

My website is mostly Perl and when someone logs in, I record the session in a database, and write it to a cookie. So whenever a person goes to the main page of my website, I show them either signed on or off. If the person goes to a page that you must be signed on for, I give them a default "You must be signed on" screen.

Anyway, the point is that the code is simple, and it's worked for a good two years.

Today I was at someone's machine where the "Am I signed on or off" feature failed. However, it only failed on two pages. On every other page it worked!

And here I am thinking, how can the same code fail on two pages, but not others. Because from every page it's called the same way, as one function, and that function comes from ONE module that all my pages use.

It's a customer's machine so I can't sit there and ask for a lot of time on it. All I could do was come home, load up Firefox, make sure I had every extention, and try to create the failure here, and no way.

So my general question is has anyone ever encountered something like this? Maybe in Firefox, or the likes?

Forgive the generality, it just makes no sense to me.

Thanks ahead,

Sergio