Error when creating installer: Unable to create the store directory.

Why would the following error happen?

```
Error: Failed with exit code: 1
Output:
Attempting to build package from 'CommercialTribe-Companion.nuspec'.
lib\net45\resources\app.asar.unpacked\node_modules\ffmpeg-static\bin\win32\ia32\ffmpeg.exe
Unable to create the store directory. (Exception from HRESULT: 0x80131468)
at ChildProcess.proc.on.code (C:\projects\companion\node_modules\electron-winstaller\lib\spawn-promise.js:62:16)
at emitTwo (events.js:106:13)
at ChildProcess.emit (events.js:191:7)
at maybeClose (internal/child_process.js:886:16)
at Process.ChildProcess._handle.onexit (internal/child_process.js:226:5)
```

Start by reproducing the installer build that packages CommercialTribe-Companion.nuspec and inspect the failure reported through lib\spawn-promise.js:62. Check the packaged ffmpeg.exe path and determine the cause of the “Unable to create the store directory” error; done means the cause and a reproducible fix or documented requirement are established.

Written by the indexing model from the issue text.