Hi Archie,
I have attempted all the fixes that you suggested - thank you! Unfortunately, nothing has worked!
Out of desperation, I contacted our hosting company VentraIP and they did some investigating and found that the issue is on Quickbooks side. It appears that Quicksbooks IP address has been blacklisted and as such it is being blocked. My hosting company have advised that Quickbooks will need to delist their IP from the blacklist before my issue will be resolved.
Please find below their response to me. Would appreciate some assistance in getting Quickbooks IT to attend to the blacklisting issue to get their IP delisted please as soon as possible please:
Hi there Larisa.
Thanks for your reply.
Unfortunately it looks like one or most of their sending nodes are listed on a spam providers blacklist called Spamcop.
This is getting rejected by SpamAssassin which gets filtered before any filters are applied.
As such whitelisting their sending domains does not actually help the cause.
You would, unfortunately, have to contact Quickbooks and then ask them to delist their IP from the blacklist
If you provide the URL to their support:
ADDRESS PROVIDED IN THE ATTACHMENT
They should be able to follow the steps to delist the IP. Unfortunately due to the way that this is being filtered, we cant actually ignore this list or whitelist specific IP's.
Once that's been delisted, your issue should be resolved.
Let us know if you have any questions or concerns.
Regards,
