@Clueless1: In order to transfer files to and from your S10 to your PC, I recommend using Smart Switch. With this in mind, please follow the link below and click on 'How do I get Smart Switch on My PC or Mac' to download the relevant version.
Once installed, open Smart Switch, connect your phone using your USB cable, and you should be good to go.
I now have the same problem, it worked fine in the past now so I know it's not a cable or PC problem, I get the same problem, phone charging but Not seen by PC, Smart Switch doesn't see it neither and have re-installed it twice. Don't know when this started to happen, could this maybe have been caused by a Windows 10 update or a Samsung S10 update
Probably, the drivers for Samsung/ Android devices are not installed on your Windows PC.
You can manually download and install them from here:
Thanks Ayybee but I already had the Samsung USB driver installed but I downloaded this one just to see and it made no difference at all.
I would have assumed that the latest Samsung driver would have been installed with Smart Switch anyway.