We apologize for the inconvenience caused, as per the description above, the Send File button in Acrobat Pro DC is not working and you are unable to send any PDF file using the Send button, Is that correct?
Please check for any pending updates of Acrobat Pro DC from Help menu>Check for updates, installed the latest updates if any, and reboot the machine, and see if the latest updates bring any difference.
You may also repair the Outlook 2010 from Programs and Features and select the Repair option for Microsoft Office. Run the repair and restart the machine.
You may also refer to these KB docs and can try the troubleshooting steps email button doesn't work
Let us know how it goes.
I ended up repairing outlook and this fixed the issue. I hope this helps someone in the future.
Great! Good to hear that the issue got fixed by repairing the outlook, and thank you so much for sharing the workaround as it's definitely going to help others.