D90D7 WES7 Intermittently Fails To Install USB Flash Drives on 20 thin clients

D90D7 WES7 Intermittently Fails To Install USB Flash Drives on 20 thin clients

I have 20 Wyse D90D7s (all purchased at the same time) running in a computer lab. They run the stock WES7 that came with the systems and are managed by WDM 5.0.

My problem makes no sense. How can a drive be recognized by WES7 on some thin clients but not others? How can it work on the same system one day, but not the next? Why can I manually install them with a DISKPART scan sometimes, but not every time? I feel like an insane person.

My problem is that these systems are causing a MAJOR headache for instructors and myself since they randomly decide not to install the USB drives that students bring with them. For example, in a class of 20 students who all sit in the same place every class, anywhere from 2-5 random students will complain that the computer does not recognize their USB drive when they plug it in. I go check and, sure enough, the WES 7 environment does not install the drive after it is inserted in to the front USB ports (or back; it doesn't matter which). I can reboot with the drive still plugged in and some times the system will recognize it and start installing; other times it doesn't until you remove and re-insert the drive after rebooting a second time. The students will say it worked for them last time, but not this time. And every time it seems to be different students. This makes no sense.....

FBWF is disabled on all systems and I made the Wyse account an admin to eliminate that possibility. A random drive will fail to install automatically on one D90D7 and you can take it to the exact same config at the desk next to it and it will work without any problems. It does not appear to be specific to any drive make/model.

To break down my list of problems relating to USB Drives:

1. Intermittent - sometimes the same system will recognize the same drive one day, and not the next.
2. Sometimes drives will be recognized after a reboot; other times you have to pull the drive, reboot, and then re-insert. Sometimes they are never recognized until I log in as admin and try again.
3. The local Wyse user is admin and FBWF is disabled
4. USB Redirection to VDI In A Box seems to work fine as long as the drive is recognized by WES7.
5. I can manually run DISKPART from CLI after inserting a disk that fails to install and it will install without problems. This works maybe 70% of the time.
6. ALL drives show up in Devices and Printers, but the ones that do not install have a yellow Alert icon next to them. When I run troubleshooting to try to force the drive install, the install fails EVERY time.
7. Students have many different types of drives and have never had problems before we upgraded to the D90D7 running WES7 (previously used old desktops with Win7 Pro as thin clients), so I am 100% certain that there is either a configuration issue (which doesn't make sense since the problem is so intermittent) or a software issue with WES7.
8. All devices are completely up to date with windows updates, Wyse firmware, HAgent, and everything else I could think of.

Thank you to anyone who can resolve this problem once and for all.... Troubleshooting has been a massive pain since everything seems to work fine for me one day and not at all the next... despite no changes in system states day-to-day.

Currently I have a "work around" that seemed to be working great for a week and now i get a call saying more people are having trouble today... The work around is a script on the desktop that initializes the DISKPART command to re-scan hardware and, if that fails, to re-seat the drives and reboot.... Not at all a professional solution but the only thing I have that seems to work about 90% of the time!