Did you change your email password?
If you changed your email password, you will need reestablish connection between your email and Quickemr.
This can be done under Settings->Email/Fax

Gmail Account Users: Updating Password
1. Will need to delete their existing account within QuickEMR under Settings->Email/Fax
2. Go into their gmail security settings and ensure that access has been removed from Quickemr
3. Input their Gmail account back into quickemr and sign in with the updated password

Other Provider:
If you inputted the password and email address correctly and your email is still not sending, try other provider and input your server address, port, and auth method
If the user is using a web hosting service such as GoDaddy
You will need to select other provider within quickemr and input your server address, port, and auth method.
You may also need to allow smtp settings for your email(s)

Visiting "Schedule" => "E-mail Reminders" or "Reports" => "Logs" => "Reminder E-mail Logs" will show if the e-mail was "sent". There is currently no way to verify if the e-mail is received. While some marketing system use a few tricks to confirm receipt even these are not 100% reliable.

If anyone on the list is getting e-mail then the problem is not with QuickEMR.

Steps to fix if "some" people are not receiving their e-mail reminders:

1. Make sure the correct e-mail is on file in the patient record.
2. Make sure the patient in question has checked their junk e-mail filter manually and added the domain to their safe sender list.
3. Make sure your e-mail message content is personalized (e.g. use tokens to insert the users real name).
4. Make sure the e-mail does not contain Spam phrases (e.g. "You could win $100") or misspellings, vulgar, or inappropriate images. All of these may trigger a Spam filter.
5. Make sure you only send e-mail to people who ask for it. Every time someone sends an e-mail from your domain to a Spam folder it lowers your "reputation" triggering auto-spam filters.
6. Make sure you use an e-mail service provider with "good" reputation. Hotmail is commonly blocked due to abuse of that domain and it's IP addresses in the past. Instead use office365, google, or someone with better reputation.
7. Check with your IT department and make sure they have set up your SPF record to accept e-mail sent from QuickEMRs web server: 162.217.193.67