How can I disable exe using vb6?

The question and what you possibly may want makes no sense at all.
Don't create EXE file!

You don't explain the use of this executable.
If your purpose is to prevent accidental run of this file, one simple trick is: rename its extension part. The file still can be loaded run as application via a call to CreateProcessEx explicitly (file name does not really mean anything special as well as its "extension" part) but it won't be accidentally run on click by the Shell.

—SA

You could do something like this:

1. Encrypt the original exe
2. Have a stub exe in VB6 that prompts for a password
3. If the password is correct, decrypt the original exe and run it
4. If the password is wrong, show an error and exit
5. You can also have a version of the stub executable that uses windows auth to run the executable (and you can have a pre-decided list of allowed users)

Applicable: VB6 & VB6 Created Exe files

This a Not a robust trick: Some Anti-Virus programs won't allow this and they will detect the scrambled exe file as virus

PUBLIC FUNCTION ScrambleVbExe(Fname as string, DoIt as boolean)

Dim sBuffer As String
Dim FN As Integer
FN = FreeFile

Open Fname For Binary As #FN
sBuffer = Space$(LOF(FN))
Get #FN, 1, sBuffer
Close #FN

if DoIt=true then
sBuffer = Replace(sBuffer, "MSVBVM60.DLL", "PREVENTMYRUN")
else
sBuffer = Replace(sBuffer,  "PREVENTMYRUN", "MSVBVM60.DLL")
end if

Open Fname For Binary As #FN
Put #FN, , sBuffer
Close #FN

End function

If you want to prevent the executable from being started, just open it and write a character in the file.