Hi Sunnysue,

Thanks for reaching out. It was a relief to know that I was not the only one experiencing this issue, as I felt it would only be resolved if more users experienced it.

The good news is, I checked spamcop.net today and it was the first time in the last 10 days that the QBO IP address was not showing as blacklisted. YAY! So I went ahead and resent my test invoice and finally the invoice got through. 

Hopefully the blacklisting issue has been fixed permanently and this not just a temp fix till the IP gets back onto the blacklist.

All the best, reach out and let me know how you went.

thanks