Microsoft products such as: Internet Explorer (Edge browser) and Outlook can sometimes display problems when loading Email To Notes (bcc) code from Salestrekker duo to compatibility issue.
This can happen either when you click on email address of Contact in Salestrekker and that opens Outlook as preferred mail sending program or when you manually copy code to clipboard and paste it. In both cases you would have "undefined" writen where deal Email To Notes code should be.
We advise you to use Google Chrome as browser instead of Microsoft Edge (or Internet Explorer). This should solve code generating and posting issues altogether. If it still doesn't work then try switching to alternative email client (Gmail, Mozilla Thunderbird...).