I had an attempt at this yesterday evening after hours.
Our file is online only. It used to be possible to just go offline, then back online from within the file but this function was removed with an update some time ago.
I did manage to create a separate offline version of the file & that allowed me to access the print/email invoices lists.
To clear the unsent email invoices list requires much more time than I had last night though as I will have to manually change the 'send to' address on each one individually. (Many of our customers will not be happy if I load up their inboxes with two months worth of past invoices, so the only way to clear them seems to be to send them to my own email address). Each time I change the 'send to' address it also pops up with a 'Do you want to update email contact details for this customer' etc...so it's will be a very tedious & time-consuming process when there are many invoices to clear.
I tried doing just a few to see if it would work but the offline version of our company file would not allow me to email. I would either need to spend more time setting up the email functionality in the offline file, or it's just not possible to email from an offline file? - not sure which & perhaps you can enlighten me on if that's possible or not?
IF this is the only way to fix the issue (ie by creating a separate offline file from a backup, going in to the offline file to clear the Print/Email lists, then restoring the offline file over the top of our online file) then I need to do it after hours over the weekend as it's going to take quite some time.
Is there any other way to bulk-clear unsent email invoices other than emailing them? (Note: it is the 'Email Invoices' which now has a large backlog to clear. There were only a small handful of unprinted invoices sitting in the 'Print Invoices' list.) Can they be purged from the 'unsent' some other way?
What is the root cause of the issue? I'm assuming the diagnostic gave indication of the cause? Is it an internet speed issue? Something else?