Explorer.exe doesn't come up on startup.

[Gunther]

Hi,

My shell doesn't come up on startup after I login. I have to press
<ctrl> + <alt> + <del>, file, run, type explorer, then <enter>. How do
I make it so that it comes up on startup again?

I checked this key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows
NT\CurrentVersion\Winlogon There is already a shell with explorer
specified.

I tried this, no luck.
sfc /scannow

When explorer is opened manually, Data Execution Prevention closes it
at random.

I downloaded a trial version of a shell from http://www.astonshell.com,
it works fine, uses a bit of system resources, but still the shell
doesn't come up on startup, I have to manually open it too.

 

[Gunther]

Please help!