Chris
its laughable that customer services say they are unware of any problem. They ought to be.
It sounds like the same issue as we have been having for much of the last 4 months. Because QB have a poor reputation as senders of spam a number of servers are blacklisting.
This doesn't affect all e mail servers only some. QB had advised earlier in this thread it would be fixed by 6th June - it has not been.
QB have not responded since then to this thread - presumably they are just clueless as to when this will get fixed.. or maybe just clueless..
Our workaround was to use a different domain for the company details in QB - a gmail e mail account for example - the invoices will then hopefully come to you so you have a record - otherwise they will show as undelivered.
it may be that your customers are receiving invoices - the undelivered can apply to just your e mail not theirs.
If any customers are also blacklisting QB then the only option is to manually e mail them out.
I hope this assists you in understanding the issue and a possible workaround - meanwhile the frustration on the complete lack of any customer service and refund/compensation is disgraceful.
Eventually people will vote with their feet and go elsewhere
