I have seen issues where registering with whatsapp server sometimes fails when using yowsup with old_version error (Yowsup - old_version error). I understand this is due to whatsapp upgrading itself, what is a good way to find latest MD5, KEY and VERSION that whatsapp uses so that yowsup can register without an issue.
follow these 3 simple steps:
This should solve the issue
You can use this site: https://coderus.openrepos.net/whitesoft/whatsapp_scratch
This site provides the MD5, key and the version.