Could the problem be caused by blocked cookies in the later case?

>A strange one involving IE - no it's not an option to change the web browser or security settings on the user machine
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>This is the problem - it only affects IE and no I don't know what version my users are using - there are too many of them
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>If I load up domain www.mfcourier.com and select online bookings I get a login screen which allows my users to login and complete a web booking - the login url is http://www.northwayweb.com/mflight/newsite/client_login/index.asp
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>If I load up domain www.maillaposte.com which is forwarded to http://www.northwayweb.com/mflight/newsite/client_login/index.asp I get the same login screen but the user cannot login
>
>Am I correct that the maillaposte.com site has some security settings which need to be changed?