Try browsing to -
C:\Users\Username\AppData\Roaming\Microsoft\Windows\AccountPictures
Replace 'username' with your own. All account pictures should show up in here. If nothing there, try -
C:\users\Username\AppData\Local\Packages\windows.immersivecontrolpanel_cw5n1h2txyewy\TempState
Again...
Had this problem too, was able to fix it by doing this -
a. Open Control Panel
b. Open 'Troubleshooting'
c. Select 'fix problems with Windows updates'
Allow it do do any fixes then try installing app again. Hope this helps.