problem in user authorisation with SAPGUI for HTML

Hi All,

I had connected to SAP production system through Trasactional Iview by making use of SAPGUI for HTML.On previewing the iview it again gives the screen of SAP WEB Application Server with portal SID and ask for credentials to connect , on providing the sap* user id and password it says logon not possible , as below :-

" <b>Client, name, or password is not correct; log on again</b> "

while the SAPGUI for windows it's working fine .

Kindly advice.

Pratap