To prevent its use as a production operating system, Windows PE automatically stops running the shell and restarts after 72 hours of continuous use. This period is not configurable.
Windows PE doesn't support any of the following:
File server or Terminal Server use.
Joining to a network domain.
Connecting to an IPv4 network from Windows PE on an IPv6 network.
Remote Desktop.
.MSI installation files.
Booting from a path that contains non-English characters.
Running 64-bit apps on the 32-bit version of Windows PE.
Adding bundled app packages through DISM (.appxbundle packages).