Having trouble with my connection to my 996Xt using FreeScan and Windows 10. Checked Drivers and Port speeds, etc.
Have no issues with Sentinel or ARCPRO for my 536 and SDS100. Connection is fine for downloads and Scanner control.
I uninstalled FreeScan and re-installed the software. And, I have Seriel to USB cable.
What am I doing wrong???
In FreeSCAN, have you tried the "Auto" function to see if the software can find a serial port? )I presume the ARC software has something similar, but I do not have that software. I use ProScan and FreeSCAN.)
Is your USB to Serial cable one of the newer ones? or several years old. From what I've seen noted, some of the USB to Serial convertors are using an older chip, that is not supported by Windows 10. That also applies to Uniden's USB-1 cable. The original version does not work on Windows 10 PCs. There is a newer version that does.
Have you looked at the Device Manager for your PC? Go to the Contro Panel to access the Device Manager, then click on the Ports link to expand it.

My desktop has an actual Com port. The Com6, uniden Serial Port, is the one created for the x436HP, SDS, and P2 series Uniden scanners (The "P2s" are the BCD325P2 and BCD996P2).
The port labeled Com 8 is the USB to Serial cable used by the GRE & Whistler scanners. If your USB cable is working, it would be listed there. But if it is listed, with a yellow triangle by it, then it is not working.