A bit of digging around shows that Adobe is aware of this bug and is still working on a fix.
This issue with the latest Adobe Flash Installer giving this type of error is linked to a system with no Drive C. Workaround
Plug in a USB storage device
Windows will then assign it as Drive C (if it is not automatically assigned this drive letter, go to computer management and assign it manually)
Run the installer Note:
You can use any type of media as long as windows can recognize it as a storage device (ex. SD cards, External HD, etc.)