Installation & Update Issues

Installing an Add-on should be a straight forward and easy task. But despite our attempt to make things easy, sometimes things go wrong. This Guide is a collection of Issues which have been reported by others. Ok, we have only one issue by now, but we add them as they get reported.
Don’t Panic. Your problem can be fixed.

DLL load failed: %1 is not a valid Win32 application

This happens on Windows when your Blender Application Data folder is corrupted. We never found a good reason for when this happens, but it does happen.

Note: This issue is also documented in the Blender manual


Clean up your Application Data. You find the data here:

C:\Users\<username>\AppData\Roaming\Blender Foundation\Blender\<release>


Sometimes another Add-on installation pollutes the Application data folder with scripts and libraries from older blender versions. This can easily make it impossible to install another Add-on. We ensure that our Add-ons never creates such sort of pollution. And here is how you can get out of this issue:

  1. Locate the Blender Application data folder (see above)
  2. within the folder locate the subfolder that is named like your Blender release, for example:
     Blender Foundation\blender\2.77
  3. rename this folder to something like
     Blender Foundation\blender\2.77_hide

    Note: The name is not important, use whatever is convenient for you. You even can delete the folder if you like, but see below!

  4. Now restart Blender

This will cleanup your application data folder. But take care! This resets blender to its Factory settings. Any other Add-on that you have installed is no longer visible and you need to install them again. However you can use the hidden subfolder ( 2.77_hide in my example) to recreate your installation. Although in most cases it seems easier to install all of your Add-ons again.

When the update fails

When you update an Add-on in Blender, then normally the following steps are performed:

  1. The installer disables the current version of the Add-on.
  2. The disabled Add-on is removed from the system (deleted from disk),
  3. The new Add-on version is installed.
  4. You now can enable the new version manually

However sometimes the first step (disabling the Add-on) does not disable all of the software. So it may happen that the old Add-on leaves some traces which may result in subsequent errors when the new version is enabled in step 4.

When the above situation happens to you, then please proceed as follows:

Step 0: Remove traces

  • Save User Setting at the bottom of the User Preferences Panel:
  • Then close Blender
    It is important that you really close blender.
    Opening a new scene or pressing F8 are not enough!
  • Open Blender and open the User preferences again
  • Type “Avastar” into the Add-on search field to locate your Add-on
  • Then Enable the Add-on

In most cases this is all that you need to do. The Add-on will enable without errors.

If the above procedure does not work for you, then you need to put blender into a clean state as follows:

Step 1: Remove Avastar

You find the Remove Button in the expanded Avastar Add-on Panel:

Step 2: Save User Settings

You find the Save User settings Button at the bottom of the User Preferences Window:

Step 3: Restart Blender and Install the new Avastar Add-on

Proceed by installing your Add-on: