Last error code set: AIF is in an undefined state, that is not safe to be upgraded, reason Upgrade wasn't completed

Error : 
SAP SUM SP Upgrade --> Extraction Phase -->PREP_INIT\VALCHK_INI

This issue occurs if you have deleted your old SUM folder because you hit error and ran afresh.

Solution
Whenever you delete SUM folder  don't forget to delete SIGNATURE.SMF

Extract new SUM and a new signature.smg will be generated.