[Slackbuilds-users] Email rejected during submission

[Daniel Prosser]

Trying to submit an update to one of my SlackBuilds, I get this error:

*****
[my email address] was rejected by mx2.hotmail.com.
Go back and enter a valid E-Mail address.

If your mailserver uses Greylisting you may want to Whitelist
slackbuilds-users at slackbuilds.org.
*****

I have added slackbuilds-users at slackbuilds.org and also the
slackbuilds.org domain to my safe senders list. Anything else I can do?
This has never happened to me in the past.

Dan