could not login to customer portal from my registered machine

Obviously I am logged in but this is from another linux machine which is not the one I registered for support.  When I logged in from that machine, I got "Internal Server Error".  "The server experienced a problem which prevented your request from being filled out.  It may not be possible to execute this action at this time.  Please help us correct this problem by <link>contacting us with details of how you recieved this error."  Clicking on the link went to a document page. 

Since I was already logged on from one location, does it not allow multiple logins?  Or is there something with my setup it is hanging up on?