What would cause Windows to deny access to a network share?

[beer]

Both my laptop and my roommate's computer, running Windows XP, and my brother's computer, running Windows 2000, cannot access my network shares.

Both computers can ping and see each other. Neither of them is on a domain.
Both computers are clean of any firewalls and viruses.
Both computers are Windows XP (my bro's is 2000.....same thing).
The network share in question returns an 'access denied' with both the 'everyone' group as well as the exact same user name and password specified on both computers.

What could be causing the 'access denied' message?

 

[EeyoreX]

The simplest thing I can think of is that either 1) you don't have the users granted proper access or are not entering passwords. Or 2) the guest account is disabled on the PC sharing the files AND condition 1 is met.

\Dan

 

[beer]

I have made sure that the users are authenticating as local users, not as guests - it is a setting in the Local Security Policy.

Technically, authentication shouldn't matter because this is happening with the 'everyone' group as well as individual users who have matching names/passwords on both computers.

 

[DJFuji]

do you have a deny setting that is overriding any "allow" settings?