I'm wondering if anyone else has had this problem, and hopefully a solution. 

Issue: When downloading to the panel, it connects, shuts the runtime down if running, and seems to download for a bit, but then I don't see any traffic on my network connection and TIA just sits with the "Loading Configuration" pop up until I cancel and disconnect the cable. I've let it sit over an hour sometimes. 

Work around: I have been able to eventually work around the issue by rebooting then switching to an Ethernet download, and if that fails reboot and try a PN download. Sometimes it takes a few tries back and forth. 

Further Details:

I have had quite a few 10" MTP Unified Comfort Panels (>10) that I have troubles downloading too. Brand new panels, update to latest image with ProSave (I started noticing issue around 18.0.0.1 and this week with 18.0.0.3). Using TIA Portal V18 upd3. Same issue on a Windows 11 and a Windows 10 laptop. Connected directly from HMI to Laptop with ethernet cable usually, but sometimes through a remote VPN.

I originally had this problem with the same project downloaded to each panel, but I just tried a fresh project with only a single panel, added a simple Hello World screen, disabled encrypted download, and had the issue. 

Hello ndoell

I worked with different Unified Comfort Panels and also different Update versions of V18 and do not have the problems you describe... but if you tried it with a fresh project and with different panels then a reset of IM folder or reset to factory settings of the panel will probably not help.

Do you already have tried to contact Siemens Support and open a Service Request?

Bye Murof