Emails with Embedded links to files on Google drive are not delivered

I'm having an issue that I need help with. I use Xfinity for my internet and main email. If I send an email out with a link to a file stored on google drive embedded in it, it is never delivered (no errors and it doesn't end up in the receivers spam folder - it just never gets there). I have tried this over and over and I have discovered that the problem seems limited to Google drive links. I have html links in my email signature that get through all the time and have tested emails with web page links too with no problems. Also, if I send the same email with the link to the file on google drive from my Google email, it works fine. So it is a Comcast/Xfinity issue and occurs when I have embedded a link to a file on my google drive. Any ideas/steps to further troubleshoot or fix?