API Key not received – plugin therefore worthless

I just installed the SUCURI Plugin and was hoping to test it by using the promissed free API-Key. I just needed to select the appropriate user account (Admin-Account) and the key would be sent to the associated e-mail address. This did’t hapen – so either the e–mail went to SPAM (none received so far) or just into E-Mail Heaven. I’ve tried the e-mail functionality of my server and WP-Installation – works fine, just not for SUCURi.