How can I get multiple batch email addresses to be separated by a comma, not a semi-colon, which will not allow my system to read the addresses?

We only accept the comma separator in entering multiple emails, Captppan. 

If we enter multiple emails without a separator or a different one, we highlight it with red to verify it further. We can place the comma right after the domain, or a space in between the comma. This applies to all transactions and I used an invoice as an example for my screenshot. 

It's possible that a browser cache issue might have cause that we're unable to accept the comma separator. We can verify it by accessing QuickBooks using a private browser. Then, let's enter the email again separated with a comma. 

If it worked fine, we can switch back to our main browser to clear cache to remove those stored files causing the unusual behavior within QuickBooks. Other browser can also help us in getting rid of browser-related issues since they store different cache folders. Browser such as Google Chrome, Internet Explorer, or Mozilla Firefox. 

Keep me posted on how this works. I'm here to keep an eye on it.