Error message - table not connecting

[tuckertoo]

My students are using Chromebooks and Samsung tablets.  Most students can connect with no trouble but I have a few who are getting the attached error message on their computer and a blank screen on their tablet.  This happens with tablets that work perfectly for other students and it happens regardless of what Chromebook they use.  Is it possible that there is a setting in their App Inventor account that is causing this?  I'm open to trying anything to help them.  Thank you!

[TimAI2]

This looks like a mixup between versions/releases of AppInventor?

Are all the Chromebooks and Companion Apps on devices fully up to date and running the latest versions?

For the Companion App use the one found in Appinventor browser program : Help : Companion Information: 2.51a or 2.51au

[tuckertoo]

I figured it out.  The accent color on the main screen needs to changed to default.  I hope this helps anyone who was having the same problem.