When the user is trying to run Section wizard from STAAD.Pro it gives an error - Section.exe "The program can't start because NGWinsys.dll is missing from your computer. "
Locate the ngwinsys.dll file in your machine.
Rename the “ngwinsys.dll” file in the C:\windows\system32 directory if it is there.
Download NGwinsys.dll from any other machine and paste it in C:\WINDOWS\System32 folder, in case the file is not there.
If this does not work, uninstall STAAD.Pro and reinstall it. If this is a Windows Vista/7/8/10/11 machine, right-click on the .msi/.exe file and select the option "Run as administrator" (though you are logged in as the administrator.