TermDD Event ID 56

hello,

we have windows 2008r2 sp1 terminalserver, running on windows 2008r2 sp1 hyper-v server.
on every terminalserver following eventlog entry daily multiple times (between 3-8 times):

the terminal server security layer detected error in protocol stream , has disconnected client. client ip: xx.x.xx.x
log name:      system
source:        termdd
eventid:    56

our users disconnected session when working on terminalserver. users using remoteapps.
users have installed rdp 7 on windows xp or windows 7 clients.
users working on same lan terminalserver or vpn access (site site vpn, ipsec).
both users, on lan , vpn, affected.

so looks not vpn problem. users not disconnected same time. have tried updating nic driver on pc, no effect.

i have tried add regkey enablepmtubhdetect under hklm\system\currentcontrolset\services\tcpip\parameters\

maybe can us?

maybe has similar problems? using vpn sonicwall devices, but, problem seems exist on lan without vpn....

regards

hi,

it is more nic driver issue. if problem affects multiple workstations please start updating network card firmware , drivers on hyper-v server, restart, , see if problem resolved.  for example, if dell server download latest system update utility (suu) dvd .iso server model , let apply updates recommends network card drivers, system bios, etc.

after installation,if possible,recreate virtual switch , combine updated nic see whether issue can resolved.

if issue still persists,on 1 of workstations being disconnected frequently, open command prompt , start conitnuous ping:

ping server.domainname.com -t

periodically press ctrl-break in command prompt window see ping statistics.  check see whether there request timed out messages. then, need find out ways optimize network bandwidth.

regards,

clarence

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Windows Server  >  Remote Desktop Services (Terminal Services)