Enabling Short Filenames In Windows so that PropView can Interact with the VOACAP Prediction Engine

tnx to John W1JA for the information in this article

The VOACAP propagation prediction engine employed by PropView is the result of decades of US government-funded HF propagation research stretching back to the dawn of computing. While VOACAP's forecasting capability has been continuously improved as knowledge about HF propagation has increased, its software technology is firmly rooted in the 1980s. In particular, VOACAP requires all filenames to conform to the Microsoft DOS 8.3 format. By default, the DXLab Launcher installs PropView in


All three of the folders in this pathname - C:, DXLab, and PropView - comply with the 8.3 format. However, if you've directed the Launcher to install PropView in

C:\Ham Radio\DXLab\PropView

the Ham Radio folder in this pathname is problematic. Windows provides a workaround for this: it can automatically generate a 8.3 compliant short filename that can be used in place of a non-compliant filename like Ham Radio. PropView automatomatically uses these short filenames when preparing the script file that drives VOACAP predictions and when specifying the file into which VOACAP is to place its numerical results. None of this requires any attention or even awareness from the user.

However, Windows provides the ability to disable the use of short filenames on a disk volume basis, and on a computer-wide basis. If short filenames are disabled, then when PropView directs VOACAP to generate a forecast, the Main window's Prediction tab will display ...computing, but never produce the requested forecast.

You can use Windows' FSUTIL utility to determine whether short filenames are enabled or disabled, and re-enable them if necessary. The FSUTIL.EXE utility must be run in a Cmd window, and -- depending upon your system's security settings -- may require being run from a Cmd window with Administrative privileges.

If PropView is installed on your system's C: volume, this command will reveal whether short filenames are enabled on that volume:

FSUTIL.EXE 8dot3name query C:

The response when short filename creation is enabled on volume C: is

The volume state is: 0 (8dot3 name creation is enabled).
The registry state is: 2 (Per volume setting - the default).
Based on the above two settings, 8dot3 name creation is enabled on C:

The response when short filename creation is disabled on volume C: is

The volume state is: 1 (8dot3 name creation is disabled). 
The registry state is: 2 (Per volume setting - the default).
Based on the above two settings, 8dot3 name creation is disabled on C:

Enabling short filename creation on a disk volume

If FSUTIL.EXE reports that short filename creation is disabled on volume C, you can enable it with the command

FSUTIL.EXE 8dot3name set C: 0

If you have PropView installed on a volume other than C:, specify the appropriate volume letter.

Enabling short filename creation computer-wide

If FSUTIL.EXE reports that the registry state is 1, meaning that short filename creation is disabled computer-wide, you can enable it with the command

FSUTIL.EXE 8dot3name set 2

and then reboot Windows. Use FSUTIL.EXE to confirm that computer-wide short filename creation is now enabled.

Enabling short filename creation for already-created folders

The above actions will enable new folders created on a volume to provide short filenames, but an already-created folder -- like the one in which PropView has been installed -- will not have a short name since shortname creation was disabled when it was created. If, for example, the Launcher installed PropView in

C:\Ham Radio\DXLab\PropView

then execute this command from a Cmd window to create a short name:

FSUTIL file setshortname "C:\Ham Radio" HAMRAD~1

where HAMRAD~1 is a unique 8.3-compliant name.

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WindowsEnableShortFilenames (last edited 2018-03-30 22:20:16 by AA6YQ)