VEXos not connecting to brain

Hi there,

I’m having problems getting VEXos to connect to my robot brains.

It keeps saying USB connection failure in normal switch on mode.

In DFU mode, VEXos doesn’t seem to detect anything.

I’ve looked in device manager and found a virtual COM port when the brain is switched on

but there is a pop up saying the device drivers were not successfully installed.

Please can you advise how to overcome this issue?

My students are desperate to get going with programming.


Can you post what version of Operating System you are running?

Assuming Windows when you did the install did you do it as Admin? Was there any warnings when you did the install?

Going out on a limb, is this a school managed PC? Some schools have USB blockers to keep students from plugging weird things in.

Thanks for your reply.

I’m running Windows 7.

RobotC was installed by Admin and VEX0s was installed after the admin used there username and password when requested.

I’ll ask about the USB blockers but I haven’t had problems using a pen drive or mouse etc.

Any other lines of attack would be greatly appreciated.

The rest of that post might help, too.
I have had to completely delete and reinstall the device drivers, and VEXos. Were these fresh, first-time VEXos and RobotC installs from latest version downloads?
And trying a different USB port on a (Dell) Win7 laptop actually has helped several times…
Also, there is Robot Mesh, and Modkit…

I had to reinstall VEXos on one laptop earlier this week as the drivers had gone AWOL. After the reinstall, worked fine.