QB Issue Resolution:
For 2015 you have to rely on the Apple Script bridge. QuickBooks Mac can talk to Apple Mail via this bridge. Make sure Apple Mail is your default email client (this is in Apple Mail prefs). Set up an Apple Mail account that communicates to gMail. Then have QuickBooks use this account.
If you had all that set up and it was working and now it isn’t… are you running Mac OS Mojave? If you are then you may have run afoul of permissions in Mojave. Mojave requires you to permit QuickBooks to talk to Apple Mail. This shows up as a dialog requesting your approval. If you reply No then QB can’t talk to Mail. And you won’t get asked again by the OS.
The fix to that is to quit QB and Mail and then open a terminal window and run this command:
tccutil reset AppleEvents
Then launch Mail and QB and try it again. You should be asked for permission for QB to talk to Mail via AppleScript. Allow it.
Resolution for Issue 'Cannot send invoices with gmail' available: Yes (Solved).
Source: Intuit Community forum.
Cannot send invoices with gmail: this issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.Support for Invoices
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Error Recovery for Invoices [Canada]
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