I am looking for help with the following task:

1. User clicks button on worksheet
2. Userform opens asking for username and password
3. The username and password information is verified against active directory
4. If username and password match AD, the user's initials are entered into a
particular cell
5. If username and password do not match AD, a msgbox advises the user of
the incorrect information.

I already have the userform created and know how to do the msgbox stuff, I
am just looking for the code to validate the user entered information to that
in AD.

Any suggesetions would be great.

Thanks in advance.