As GTR has noted, ProScan is much better software. It has a number of features that FreeSCAN does not, and it works for a wider number of scanners, from my SDS series scanners all the way back to the long discontinued BC250D. WHile you jave not mentioned DMR nor NXDN, should you, at some future date, decide to add one or more of those upgrades, you'll find that FreeSCAN does not fully & correctly support DMR and offers no support at all for NXDN. ProScan does have a 30-day free trial if you want to try before you buy.
The FreeSCAN error message above generally crops up for one of a couple of reasons.
If you have already loaded a programming file, then try to either re-load the same file, or another sizeable file, you might be exceeding the memory capacity. When loading a file, use the option to delete the existing programming before loading new lists.
The other time that often comes up is when FreeSCAN loses track of which scanner is being programmed. I ran into that occasionally when, say, I programmed my 330T, then disconnected it & connected one of my 396XTs. FreeSCAN was expecting the 330T to still be there, and then errored out when a different scanner was in place. Presuming that you did not try to send too many files to the scanner, without clearing memory, try this:
With FreeSCAN open & running, and with your scanner connected, click on the drop-down Scanner menu.
Select the Control Scanner option
At the next screen, the Virtual Control menu, select the Com Port Setup. (Ignore the fact that it might already show a port.)
On the Com Port Setup menu, select Start Auto.
That lets FreeSCAN "find" the port you are using, and identify which scanner is connected.and identify which one it is.
Here, FreeSCAN has identified my 325P2 as connected, and the port it can be found on.
After getting it to set the port, for the correct scanner, close those menus & try to load your file.