Windows is likely to be running out of desktop heap.
Confirm this to be the case
by looking in the log for the condor_schedd daemon
to see if condor_shadow daemons are immediately
exiting with status 128.
If this is the case, increase the desktop heap size.
Open the registry key:

{code}
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\SubSystems\Windows
{endcode}

The SharedSection value can have three values separated by commas.
The third value controls the desktop heap size for non-interactive desktops,
which the HTCondor service uses.
The default is 512 (Kbytes).
60 condor_shadow daemons consume about 256 Kbytes,
hence 120 shadows can run with the default value.
To be able to run a maximum of 300 condor_shadow daemons,
set this value at 1280.

Reboot the system for the changes to take effect.
For more information,
see Microsoft Article Q184802.