Thanks for bringing this one to our attention, bdesilva.

I appreciate you for coming up with a workaround by uninstalling the current version of QuickBooks and went back to an R3 version. The unrecoverable error when sending an email in QuickBooks is still an ongoing issue.

Our engineers are still investigating to identify the root cause of this issue, so they can apply a permanent resolution. For now, we don't have a specific time frame for when is this going to be mitigated. Rest assured, this is being taken care of.

Since you contacted our Technical Support Team, they already added you to the list of affected users. This way, you'll be notified through an email notification once there's an update on this issue.

Another workaround is to save the form/report a PDF and email them outside your software.

I've got a link here where you can find articles about managing your sales and customer's transactions: https://quickbooks.intuit.com/learn-support/en-us/sales-and-customers/07?product=QuickBooks%20Deskto....

I'm just one click away if you need a hand with running reports or any QuickBooks related. Wishing you and your business continued success. Take care always.