Update readme with guide to add hyper-v firewall rule if needed

README.md

@@ -232,4 +232,10 @@ if you get a permission denied message this verifies that the bind mount is not
 
 ```shell
 make podman-selinux-bind-hack
-```
+```
+
+#### Running Podman on windows with Hyper-V Firewall enabled requires opening port 5005 to the host machine
+
+Check if _local rule merging_ is set to _"No"_ as described [here](https://learn.microsoft.com/en-us/windows/wsl/troubleshooting#wsl-has-no-network-connection-on-my-work-machine-or-in-an-enterprise-environment).
+
+If this is the case you can open a Windows Powershell as administrator and run the script `OpenAppPortInHyperVFirewall.ps1` located in the `scripts` folder.

scripts/OpenAppPortInHyperVFirewall.ps1

@@ -0,0 +1,7 @@
+$AppPort = 5005
+$NetFirewallHyperVName = '{40E0AC32-46A5-438A-A0B2-2B479E8F2E90}'
+
+Get-NetFirewallHyperVVMCreator 
+Get-NetFirewallHyperVVMSetting -PolicyStore ActiveStore -Name $NetFirewallHyperVName
+Get-NetFirewallHyperVRule -VMCreatorId $NetFirewallHyperVName
+New-NetFirewallHyperVRule -Name Altinn3App -DisplayName "Altinn 3 Application" -Direction Inbound -VMCreatorId $NetFirewallHyperVName -Protocol TCP -LocalPorts $AppPort