Wyse ThinOS 7.1 session disconnecting

We utilise Wyse ThinOS terminals for users at my organisation.  They connect to a full published desktop based on XenApp 6.  The Wyse terminals have been really useful as they load very quickly and configuration is easy using INI file and DHCP flags.  This means we can ship a new unit out to site with zero configuration.  True plug and play in action!!!

We have started to purchase some newer terminals recently including the R10 and T10.  The R10 is a little older and originally came with 7.0 firmware.  The T10 is a newer terminal which is the replacement for C10 and S10 terminals.  It has a small form factor and can handle multi monitors very well indeed.

The T10 ships with firmware version 7.1.  We have found this to be very problematic in our environment.  Users would start their desktops and get disconnected at random points in the day.  We downgraded any R10s with 7.1 firmware back 7.0 and it fixed the issue.  Unfortunately you cannot downgrade the T10!!

To reproduce this problem I would watch the following video file from Gizmodo


After about 30-60 seconds the session would disconnect.  Our terminals are configured to shutdown on session end, which means the user would have to boot the terminal again. 

If the terminal is not configured for auto shutdown the following error would appear in the system information tab.

ICA: read error 0 from ica_frame_recv

We opened a support case with Wyse and they informed us that this issue had something to do with session reliability.  To workaround the issue you can disable session reliability in the wnos.ini file

BrowserIP=Server1,Server2 \
Application="AppName" \
Description="AppDesc" \
Icon=icon.JPG \
AutoConnect=Yes \
Username=$UN \
Password=$PW \
Domainname=domain \
Encryption=128 \
Resolution=DDC \
Fullscreen=yes \
HTTPBrowsing=yes \
SessionReliability=no \
Mapdisks=yes \
MapdisksUnderZ=yes \
LowBand=no \
UniSession=yes \

This had an immediate impact.  The testing showed no disconnects, but we like session reliability.  If a network link goes down for 10 seconds we do not want all users being disconnected!

Wyse have provided me with a limited release hotfix (7.1._126.01) which resolves the issues without needing to turn off session reliability.  This will be included in WTOS 08 which is due for release in Q4 2012.



  1. My company have a similar issue, do you have ant case number or Wyse KB with this workaround?


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