Ok, let me put together what we have by now (hope nobody mind me)

Assuming an install if key exists (still see no sense [Wink] )

code:
if keyexist("HKEY_CLASSES_ROOT\Avg.kernel")
    shell @scriptdir + '\avg.exe /s'
endif
OR , installing if key isn't found :

code:
if not keyexist("HKEY_CLASSES_ROOT\Avg.kernel")
    shell @scriptdir + '\avg.exe /s'
endif
Confused ? Me too [Big Grin]
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