Created OtherSoftwareInterop (markdown)

OtherSoftwareInterop.md

@@ -0,0 +1,33 @@
+# Background
+
+Tailscale tries to cooperate and run alongside other software on your machine, but sometimes that's not possible. Some operating systems impose limitations on how many VPN-type programs can run at once or register with certain OS-level facilities, and sometimes other software accidentally or by design breaks Tailscale.
+
+When debugging issues where Tailscale doesn't work, we generally start by trying to identify how your machine or network is different and what other software you're running on the machine that's apparently conflicting.
+
+# Are you running... ?
+
+Are you running any other networking, VPN, endpoint security, antivirus, or other security software?
+
+Any security proxy on the network/router?
+
+A non-exhaustive list of other software that may or may not cause problems, depending on OS/versions/configs:
+
+* Apple Private Relay
+* Avast
+* Clash, ClashX, Clash Pro X
+* Cloudflare Warp
+* Crowdstrike Falcon
+* GlobalProtect VPN
+* Mullvad
+* Netskope
+* PIA
+* TunnelBear
+* VMWare Carbon Black
+* Wireguard
+* ZeroTier
+
+Please let us know if you're running one of those, or similar programs. On some operating systems Tailscale is not even able to detect the presence of those programs due to sandboxing.
+
+If you let us know what you're running we may be able to advise you on how to configure things to work.
+
+Note that if your computer was supplied by your employer, it's very likely not "just a stock macOS install" or "just a stock Windows machine" and it's quite likely to be running other software.