QB Issue Resolution:
It appears you already selected your Comcast email account as the default that the system uses to send emails. With that said, your computer has saved it as the default email app for you.
I’d suggest contacting your computer manufacturer for further assistance, in case you’re still having problems changing your default email app.
Resolution for Issue 'Sending emails to customers' available: Yes (Solved).
Source: Intuit Community forum.
Sending emails to customers: 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 Customers
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