Microsoft Windows Error Code 0xC0000066: How to Fix It

Q: What causes error 0xC0000066?

Error 0xC0000066 occurs when a named pipe is busy, meaning a process is trying to access a pipe that is already in use. This can be caused by resource conflicts, corrupt system files, malware, or outdated drivers.

Q: Is error 0xC0000066 dangerous?

No, it is a medium-severity error that typically does not cause permanent damage. It may prevent certain applications from working correctly until resolved.

Q: Can I ignore this error?

It is not recommended to ignore it, as it may indicate underlying issues like corruption or malware. Following the fix steps can prevent further problems.

Q: Will a system restore fix error 0xC0000066?

Yes, if the error started recently, performing a system restore to a point before the error occurred may resolve it. Use the System Restore tool in Windows.

Q: Do I need to reinstall Windows to fix this error?

Rarely. Reinstalling Windows is a last resort if all other steps fail. Try the solutions above first, as they resolve the issue in most cases.

Abstract

Error code 0xC0000066, also known as STATUS_PIPE_BUSY, indicates that a named pipe used for inter-process communication is busy. This often occurs when an application or system process tries to communicate with a service that is already handling another request. While typically not critical, it can cause specific software or features to fail. Follow these steps to resolve the issue.