To fix 0x0000011b without making your network unsafe, it helps to know why the protection exists at all. This is the short story of PrintNightmare — and why undoing the fix is the one move to avoid.
Before mid-2021, connecting to a shared Windows printer was relaxed: almost any PC on the network could ask the print host to load a driver and print. Then security researchers published PrintNightmare, and it turned out that same relaxed path let an attacker run code on the host with the highest privileges. Microsoft patched in a hurry, then hardened the whole design over the following months. Error 0x0000011b is the visible edge of that hardening — the moment a patched PC refuses to talk to one that is still living by the old rules.
👆 The 2021 patch sequence that turned a silent vulnerability into a very visible printer error (dates from Microsoft's published update history)
The Windows Print Spooler runs with SYSTEM privileges and, by design, helps client PCs install printer drivers from the host. The flaw let a low-privilege network user abuse that help to load their own code instead of a driver — gaining full control of the host PC. It worked remotely, needed no physical access, and affected the machine doing the sharing. That combination is why the response was so aggressive.
RpcAuthnLevelPrivacyEnabled, so print RPC conversations had to be authenticated and privacy-protected by defaultEach wave was reasonable on its own. The trouble is that offices patch unevenly — and wave three only works when both sides of a printer connection play by the new rules.
A patched host now insists on the protected RPC level. An unpatched or differently configured client cannot provide it. The host does not explain all this in the dialog — it simply refuses the connection, and the client reports Operation failed with error 0x0000011b. The same refusal appears in reverse combinations and when a registry value on one side was set to the old behaviour by an earlier workaround.
Every popular quick fix that sets RpcAuthnLevelPrivacyEnabled to 0 or uninstalls the September 2021 updates is, knowingly or not, reopening the PrintNightmare-era behaviour on that machine. On a single home PC behind a router, the practical risk is small and the owner can judge it. On an office host reachable by dozens of machines — including guest laptops — it hands back exactly the attack surface Microsoft spent three months closing. Use the bridge only when patching is genuinely blocked, scope it to the one host, and give it an expiry date.
Watch the video for the practical fix sequence, then come back to this page if anyone suggests uninstalling security updates as the solution.
▶️ Watch Full VideoOn a fully patched PC, the known PrintNightmare paths are closed. The risk returns only where the hardening is deliberately reversed — for example a host left with RpcAuthnLevelPrivacyEnabled set to 0, or a machine that has not taken updates since 2021.
Because compatibility was the vulnerability. The old behaviour trusted client PCs too much. Microsoft chose a hard break: both sides patched, or no connection. Painful for mixed offices, but it is what makes the protection real.
Yes. The September 2021 hardening shipped for both (the KB5005565 family on Windows 10 and its Windows 11 counterparts), which is why the same error and the same fix order apply to both systems.