Counter-Strike 2: Fixes for Opening Required Steam Ports in Both Directions [2025]

Steam requires various ports to function properly (downloads, voice chat, matchmaking, etc.). In many Windows setups, outbound traffic is allowed by default, so you typically only need inbound rules. However, if you have a strict outbound policy (block-by-default), you must explicitly allow outbound as well.

Below is a PowerShell script that creates two rules for each port range: one Inbound and one Outbound.

Note: Adjust or remove outbound rules if your system already allows all outbound traffic.

# ————————–
# HTTP (TCP 80) + HTTPS (TCP 443)
# ————————–
New-NetFirewallRule -Name “Steam_HTTP_80_In” -DisplayName “Steam HTTP (80) Inbound” -Protocol TCP -LocalPort 80 -Action Allow -Direction In
New-NetFirewallRule -Name “Steam_HTTP_80_Out” -DisplayName “Steam HTTP (80) Outbound” -Protocol TCP -LocalPort 80 -Action Allow -Direction Out

New-NetFirewallRule -Name “Steam_HTTPS_443_In” -DisplayName “Steam HTTPS (443) Inbound” -Protocol TCP -LocalPort 443 -Action Allow -Direction In
New-NetFirewallRule -Name “Steam_HTTPS_443_Out” -DisplayName “Steam HTTPS (443) Outbound” -Protocol TCP -LocalPort 443 -Action Allow -Direction Out

# ————————–
# Main TCP/UDP ports 27015–27050
# ————————–
New-NetFirewallRule -Name “Steam_TCP_27015_27050_In” -DisplayName “Steam TCP 27015-27050 Inbound” -Protocol TCP -LocalPort 27015-27050 -Action Allow -Direction In
New-NetFirewallRule -Name “Steam_TCP_27015_27050_Out” -DisplayName “Steam TCP 27015-27050 Outbound” -Protocol TCP -LocalPort 27015-27050 -Action Allow -Direction Out

New-NetFirewallRule -Name “Steam_UDP_27015_27050_In” -DisplayName “Steam UDP 27015-27050 Inbound” -Protocol UDP -LocalPort 27015-27050 -Action Allow -Direction In
New-NetFirewallRule -Name “Steam_UDP_27015_27050_Out” -DisplayName “Steam UDP 27015-27050 Outbound” -Protocol UDP -LocalPort 27015-27050 -Action Allow -Direction Out

# ————————–
# Additional UDP range 27000–27100
# ————————–
New-NetFirewallRule -Name “Steam_UDP_27000_27100_In” -DisplayName “Steam UDP 27000-27100 Inbound” -Protocol UDP -LocalPort 27000-27100 -Action Allow -Direction In
New-NetFirewallRule -Name “Steam_UDP_27000_27100_Out” -DisplayName “Steam UDP 27000-27100 Outbound” -Protocol UDP -LocalPort 27000-27100 -Action Allow -Direction Out

# ————————–
# Remote Play: UDP 27031–27036, TCP 27036
# ————————–
New-NetFirewallRule -Name “Steam_UDP_RemotePlay_27031_27036_In” -DisplayName “Steam Remote Play UDP 27031-27036 In” -Protocol UDP -LocalPort 27031-27036 -Action Allow -Direction In
New-NetFirewallRule -Name “Steam_UDP_RemotePlay_27031_27036_Out” -DisplayName “Steam Remote Play UDP 27031-27036 Out” -Protocol UDP -LocalPort 27031-27036 -Action Allow -Direction Out

New-NetFirewallRule -Name “Steam_TCP_RemotePlay_27036_In” -DisplayName “Steam Remote Play TCP 27036 In” -Protocol TCP -LocalPort 27036 -Action Allow -Direction In
New-NetFirewallRule -Name “Steam_TCP_RemotePlay_27036_Out” -DisplayName “Steam Remote Play TCP 27036 Out” -Protocol TCP -LocalPort 27036 -Action Allow -Direction Out

# ————————–
# Additional UDP port 4380
# ————————–
New-NetFirewallRule -Name “Steam_UDP_4380_In” -DisplayName “Steam UDP 4380 Inbound” -Protocol UDP -LocalPort 4380 -Action Allow -Direction In
New-NetFirewallRule -Name “Steam_UDP_4380_Out” -DisplayName “Steam UDP 4380 Outbound” -Protocol UDP -LocalPort 4380 -Action Allow -Direction Out

# ————————–
# P2P / Voice Chat (Steamworks)
# ————————–
New-NetFirewallRule -Name “Steam_UDP_3478_In” -DisplayName “Steam UDP 3478 (Voice/P2P) In” -Protocol UDP -LocalPort 3478 -Action Allow -Direction In
New-NetFirewallRule -Name “Steam_UDP_3478_Out” -DisplayName “Steam UDP 3478 (Voice/P2P) Out” -Protocol UDP -LocalPort 3478 -Action Allow -Direction Out

New-NetFirewallRule -Name “Steam_UDP_4379_4380_In” -DisplayName “Steam UDP 4379-4380 Inbound” -Protocol UDP -LocalPort 4379-4380 -Action Allow -Direction In
New-NetFirewallRule -Name “Steam_UDP_4379_4380_Out” -DisplayName “Steam UDP 4379-4380 Outbound” -Protocol UDP -LocalPort 4379-4380 -Action Allow -Direction Out

New-NetFirewallRule -Name “Steam_UDP_27014_27030_In” -DisplayName “Steam UDP 27014-27030 Inbound” -Protocol UDP -LocalPort 27014-27030 -Action Allow -Direction In
New-NetFirewallRule -Name “Steam_UDP_27014_27030_Out” -DisplayName “Steam UDP 27014-27030 Outbound” -Protocol UDP -LocalPort 27014-27030 -Action Allow -Direction Out

# ————————–
# Dedicated / Listen Servers (SRCDS) – optional separate rule
# ————————–
# Typically included in 27015-27050 above, but you can add explicit rules:
# New-NetFirewallRule -Name “Steam_TCP_SRCDS_27015_In” -DisplayName “Steam SRCDS RCON (27015) Inbound” -Protocol TCP -LocalPort 27015 -Action Allow -Direction In
# New-NetFirewallRule -Name “Steam_TCP_SRCDS_27015_Out” -DisplayName “Steam SRCDS RCON (27015) Outbound” -Protocol TCP -LocalPort 27015 -Action Allow -Direction Out

# New-NetFirewallRule -Name “Steam_UDP_SRCDS_27015_In” -DisplayName “Steam SRCDS Game (27015) Inbound” -Protocol UDP -LocalPort 27015 -Action Allow -Direction In
# New-NetFirewallRule -Name “Steam_UDP_SRCDS_27015_Out” -DisplayName “Steam SRCDS Game (27015) Outbound” -Protocol UDP -LocalPort 27015 -Action Allow -Direction Out

Additional Notes
If your Windows Firewall is already allowing all outbound traffic (the default in many configurations), you don’t actually need the -Direction Out rules.
If you have a block-by-default outbound policy, these rules become necessary to allow Steam to connect properly.
Final Summary
Fix Microphone Access: Make sure Windows privacy settings are correct, choose the correct mic in both Windows and Steam, disable exclusive mode, and reset any corrupted Steam voice configs.
Open Steam Ports: If needed, add inbound and outbound rules to Windows Firewall for Steam’s required ports. In many default setups, inbound rules suffice (outbound is already allowed).
Check for Group Policies, Antivirus blocks, or driver issues if problems persist.
Run Steam as admin (last resort) if everything else fails, though it’s better to fix the underlying permission issue if possible.
By following these steps, you should resolve microphone issues in Steam and ensure all Steam ports are properly open for downloads, voice chat, and multiplayer features. Good luck, and enjoy your gaming!