USB Serial port connection issue

[edmonton]

Hi Application Engineers,

I am having a USB port connection issue for different USB devices. I use regular serial connection as shown below

USB devices can successfully connected for a fresh loaded program, however, 95% of times, re-connection fails once the program is stopped using a stop control in the program or by clicking the stop program button at the top left 

As a result, I have to close the program and reload it and run it.

I checked the status of the port before and after running the program, it shows as follows,

a: the port setting; b: before running the program,; c: after stop running the program.  

The connection can not be successfully as long as the status shows as C, and successful when status shows as b. I am wondering if there is a way of getting around the issue so that no reloading program is required after a stop?

Thanks,

Gu

[santo_13 · Accepted solution]

It is not recommended to stop a VI using the Stop button, this is like stopping a car by crashing into a tree.

Now, the reason you cannot open a new session is that during the last run the session was not closed/released properly. Once you fix your implementation to stop the VI properly after closing the session, you will not see this issue. In case, you could not do that, only way to release the session is by restarting LabVIEW.