Try doing it like this, maybe it'll fix it.

Before you proceed, you will need to "Show Hidden Files and Folders" as mentioned in this article:

• http://windows.microsoft.com/en-US/windows-vista/Show-hidden-files

-> Open the Task Manager by using CTRL + SHIFT + ESC shorkeys

• In the Processes tab, right-click on Explorer.exe process and select End Process
• Open the file picker via "File > New Task (Run)" and click the Browse button
• Type or Paste %USERPROFILE%\AppData\Local in the File name field (AppData is a hidden folder)
• Select the file IconCache.db and use Delete in the right-click context menu to delete the file
• After the IconCache.db has been deleted, start a new explorer.exe process via "File > New Task" to get the desktop and Taskbar back

Check and tell if its working.

thank you mha007, I've just tried your solution but unfortunately it doesn't fix the issue. Do you happen to know another fix?

Thanks!

Well here's a FIX:

https://support.mozilla.org/en-US/questions/758266#answer-146201

I followed the steps exactly as described and what do you know, it works!