Simplify3D User Forum

Attempting connection at \\.\COM3...
Permissions error connecting to port
Is there another application already connected to this port?
Error opening selected port.

In the Tools>Machine Control Panel it lists the same COM channels, and baud rates, nothing is working. Nothing changed other than the USB had been unplugged.
Any ideas?

Assuming this is windows go to device manager once the printer is connected and turned on to see what port it is using. It may not list the printer but you should see what ports are listed. 1&2 are usually reserved so it will likely be another one.
Also make sure you are not plugged into a USB3 port.

few possible issues

1. bad ftdi chip on printer (many printers came with fake ftdi chips that with different windows drivers behave badly)
2. windows tend to "lock" usb serial port from time to time and only way to solve it is to reboot the whole windows (nothing any app can do about it)
3. windows dumbed it self, unplug, plug back in and it should reinit the port