Cannot get Web Access to accept my login

[aadrummond]

I have installed express Invoice, Express Account and Inventoria. I have enabled web access and created users and gave them administrator access on a windows XP Professional pc on my home network. When I type the url http://Mypcname:96 I get a express login screen for login but will not let me login. Sometimes I get a respond the my session expired. I use my email address as username and the password that I entered into the Web access screen but I cannot login. any ideas why i cannot login to my express invoice or any other accounting modules. I have opened the ports 96, 97, 98 on my router and pc. I have doubled checked the user name/email address and passwords. I get a login screen but cannot login into the computer/express invoice.