The email acceptance rate are very depend on what you setup in the mail server and your DNS record, with this tools, you can rate your email delivery score on how well accept your email is.
Step 1 : Visit to Mail Tester Tool
Step 2 : Send an email to the email address stated on the the front page, and then click THEN CHECK YOUR SCORE button.
Step 3 : A test result page will be shown once mail-tester received the email you sent. The core will be displayed right at the center.
Scroll down to lower part of the page, mail-tester will let you know what your email is lack of, and why are you getting such score.
There are normally a few scenario that might affect the email delivery, the common reasons are:
Due to incorrect / non-existence of SPF record. You can edit your SPF record on your current DNS server that hosted your domain by following suggestions from Mail Tester page, and refer to this guide to setup SPF record for your domain.
Due to incorrect / non-existence of PTR record. You can consult with your email service provider to setup that.
Due to incorrect / non-existence of DKIM record. You can consult with your email service provider to setup that.
Due to incorrect server hostname. You can consult with your email service provider to setup that.
Due to blacklisted IP. You can consult with your email service provider to check further.
Due to In-proper subject / content of the email. Please amend your email content to avoid email being blocked by recipient part.