Connection problem after sending data to another calc

[retoa]

Hello !

This week I connected 5 times my calculator to some of my students calculators, to demonstrate how to send Apps and so on.

Twice after the calculator-calculator connection I could not connect my calculator to CK any more, CK did not recognise it. After a reset (reset button on the back) all worked fine.

Three times all worked well, no connection problems at all.

I could not identify the cause of the problem. All 5 times the file transfer between the two calculators finished perfectly and the new App worked fine.
4 times I disconnected the cable while the 2 calculators were on. The fifth I switched both calculator off, it was one of the time without problems.

Does anyone else have had problems with this?

Is there something special you should do to disconnect correctly to calculators? (The manual does not say nothing about disconnection)

Thank you very much

Reto