Portmon.exe Error 2 May 2026

To understand the error, one must first decode it. In the Windows operating system, standard system error codes are defined in the WinError.h header file. "Error 2" corresponds to ERROR_FILE_NOT_FOUND , which translates to "The system cannot find the file specified." When Portmon executes and returns this error, it is not complaining about its own executable file. Instead, the utility is attempting to access a kernel-mode driver or a device object representing a COM port or LPT port. Under the hood, Portmon installs a temporary kernel driver ( portmon.sys ) to hook into the I/O subsystem. If the system cannot locate the requested port device (e.g., \\.\COM1 or \\.\LPT1 ), or if the driver fails to load due to missing dependencies, the operating system returns ERROR_FILE_NOT_FOUND , which Portmon reports simply as "error 2."

Introduction

For a technician encountering Error 2, the solution is rarely a simple reinstall. First, one must verify the existence of a physical or virtual serial/parallel port. In a virtual machine (e.g., VirtualBox, VMware), adding a virtual COM port may resolve the error. Second, for 64-bit systems, the only reliable solution is to use an alternative, modern tool such as from Eltima Software or the built-in PowerShell commands (e.g., Get-WinEvent with query filters). Third, as an unsupported workaround, one can run Portmon inside a 32-bit virtual machine running Windows XP or older, where driver signing was not enforced. None of these solutions "fix" Portmon; instead, they accommodate its obsolescence. portmon.exe error 2