Failed to join stream: Screen Share session already registered // Screen share session fails to be established

CryptoLocker · January 22, 2025, 10:47pm

I fixed the issue for myself, my fix might be different because of my network design but these are the steps i took to get it working, my firewall Pfsense rewrites source ports on both automatic and hybrid outbound NAT by default.

Solution :

REWRITTEN by @gouthamravee

Navigate to Firewall > Aliases
Click the + icon to create a new alias
Name it teamspeak_screenshare or what ever you want
Change type to Port(s)
Paste 49152:65535 into the “Content” section
Give it a description if you want
Click Save
You can do this again and create a Host(s) alias for the device(s) running the TeamSpeak Client, that way you can screen share from all your devices without having to create additional NAT rules.
Navigate to Firewall > NAT > Outbound tab
Select Hybrid Outbound NAT
Click Save
Click Add with the up arrow to add a rule to the top of the list
Set Interface to WAN
Set the Protocol to match the desired traffic (e.g. UDP)
Set the Source to Single host or network and put the local IP address of the device you want to screen share from or select the alias if you created one before.
For Source Port select the teamspeak_screenshare alias
Leave Destination as any
Leave Destination Port as any
Set the Translation Address to Interface Address
Check Static Port to indicate that traffic matching this rule will retain the original source port
Click Save
Click Apply Changes
I didn’t have to do the steps before, but its possible you might have to. You can test screen sharing now, if you still have trouble first make sure the IP and ports match exactly as described here, and then try the steps below.
Navigate to Diagnostics > States
Enter the IP address of the device in the Filter box if a specific source was used in the rule
Click Filter
Click Kill

ORIGINAL SOLUTION

Navigate to Firewall > NAT on the Outbound tab
Select Hybrid Outbound NAT
Click Save
Click Add with the up arrow to add a rule to the top of the list
Set Interface to WAN
Set the Protocol to match the desired traffic (e.g. UDP)
Set the Source to match the local source of traffic, such as LAN Net or a specific device such as a game console IP address, or an alias containing multiple such devices
Leave the Source Port box empty, which indicates any
Set the Destination to match the traffic, if known, otherwise leave set to ‘any’
Set the Destination Port to a specific port or port alias, if it is known, otherwise leave the box blank for any
Set the Translation Address to Interface Address or an appropriate VIP if needed
Check Static Port to indicate that traffic matching this rule will retain the original source port
Click Save
Click Apply Changes
Navigate to Diagnostics > States
Enter the IP address of the device in the Filter box if a specific source was used in the rule
Click Filter
Click Kill

Source: https://docs.netgate.com/pfsense/en/latest/nat/static-port.html

The issue was my firewall rewriting the ports for the p2p and STUN connections causing the connection failures, after forcing the the ports to stay the same as the source i can now stream with all my friends with no issues. Hope this helps!