"the connection to the remote computer ended"

hi,

I have deployed vmware view/Composer/connection server <Vmware view 5.1.1 builed 799444> .i have problem of given error as some time i can connect to connection smoothly and some time it gives an error.

When i checked connection server Monitoring-Events "WARN : The pending session on machine xxxx for user xxx has expired" but i tried again and agin its connects.

I can't find the actual problem . please help me.

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It show Black screen then error " The Connection to remote computer ended"

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View Connection ->Monitoring->Error: WARAN , The pending session on machine xx for user xxxx has expired"

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But after few tries it connects smoothly as shown "Event"<Audit Success> .

Please help me to resolve problem .

Note!: my vmware view installed on VPS ( remote location ) and i am connecting to Connection server throug Firewall which redirect 443 to my internal connection server ( 10.10.10.155)  , don't install Security server)

thanks and waiting