Event ID 2021 — Psxrun Availability

Applies To: Windows Server 2008 R2

Subsystem for UNIX-based Applications (SUA) Psxrun Availability indicates the ability of the Psxrun utility to start and run SUA processes.

Problems that can occur with Psxrun Availability include API call failures, incorrect path names or command line parameters, and low virtual memory.

Event Details

Product: Windows Subsystem for UNIX-based Applications
ID: 2021
Source: Microsoft-Windows-SUA-Psxrun
Version: 6.0
Symbolic Name: NO_ANSI_CWD
Message: Unable to find 8-bit current working directory.


Check documentation and correct failure of GetCurrentDirectoryA API

During initilization of Psxrun, a call to GetCurrentDirectoryA() (ANSI version of GetCurrentDirectory) failed, either by returning NULL, or by returning a current directory that has a path character length greater than that allowed in the environment variable PATH_MAX.

For more information about requirements for calling the GetCurrentDirectoryA() API, see the "GetCurrentDirectory" topic on the Microsoft Web site (https://go.microsoft.com/fwlink/?LinkId=95089). Other articles in the Microsoft MSDN online database might also be useful.


Because multiple instances of Psxrun can be running at once, it is best to verify Psxrun in Windows Task Manager not by checking on a particular instance of Psxrun, but by verifying that the specific POSIX process or application launched by using Psxrun is running.

To verify that Psxrun is running:

  1. Open Windows Task Manager by pressing CTRL+ALT+DEL, and then clicking Start Task Manager.
  2. On the Processes tab, select the Show processes from all users check box.
  3. Verify that a specific POSIX process you have started by using Subsystem for UNIX-based Applications is running.

If the POSIX application or process that has been launched by using Psxrun is indicated as running in Task Manager, then Psxrun is fully available. If the process is not running, critical errors are preventing Psxrun from being available.

Psxrun Availability

Subsystem for UNIX-based Applications