My network key won't work on my other computer

So, my network key on 2 other computers is 8 letters long and it accepts it. On my laptop though if I enter my network key this screen pops up and says it has to be 5 to 13 characters or 10 to 26 characters. I can't change the network key obviously, it's 8 letters long.. Why won't it accept it? How can I connect to my wireless connection? The network comes up and everything I'm just having trouble with the network key.

Does this laptop use the standard Windows wireless utility, or a custom utility? If custom, what brand?

On your laptop, are you connecting to the network by selecting it from the list of connections shown by Windows?

Like so: http://windows.microsoft.com/en-US [...] s-networks

If yes, it should accept the key just fine, unless of course you aren't entering it correctly.