Suddenly Can't Send Zoho Email from Quickbooks

Suddenly Can't Send Zoho Email from Quickbooks

Every day for the past several years I send invoices to clients from Quickbooks via Zoho email.  There have been NO changes of any sort on my end.  I have checked ALL the things Quickbooks said to check and none of them are the case.  My password is correct, no firewall is blocking access, my email address is correct, I have an internet connection (obviously), I have made no changes to the outgoing port or authentication (587, SSL).  This has worked for years and now, today, inexplicably, this no longer works.  I tried changing the outgoing port to 465 but of course that didn't work because the correct one is 587.  I downloaded the latest Quickbooks release.  I got out of the program and went back in.  I restarted the computer.  Nothing works.  I'm at a loss and it is very important that this problem is solved.  I can't send invoices!


I would appreciate any help as soon as possible.


Thank you so much.