Can't add a second input because of error "Parameter name: UDP port 514 is not available" like it worked on linux

I'm sending all the logs via UDP:514 since some devices don't allow to use a different port. So I created multiple inputs all listening to port 514. Each only accepts requests from a single IP. ![alt text][1] ![alt text][2] This worked out very well while using Splunk on Linux. Trying the same settings on Windows, I am only able to create a single input. The submit of a second input does not work ("Parameter name: UDP port 514 is not available"). Is there any solution on this? [1]: /storage/temp/134211-linuxsingle.jpg [2]: /storage/temp/134210-linux.jpg