Order status is set to "Pending Order" or Canceled Order"

1. Make sure you are using a currency that is accepted by your Payment gateway provider
2. Admintools Joomla extension often create this problem by blocking Paypal IPN (you need to contact extension developer or disable it)
3. Your website must be in live production and is accessible by public visitor (not offline nor localhost)
4. Verify that you are using correct Payment credentials (api keys, security tokens, etc..). Refer to the "Payment Section" of this tutorial for detailed payment setup.
5. If you are on Sandbox mode, you need to use a sandbox credentials and enable the sandbox mode under Payments >> Preferences

Paypal Adaptive Issue

1. Make sure you have an "Approved" APP ID not Conditionally Approved
2. Vendors are required to have a "Verified" paypal account

The money is received but order status is still "Pending"

This means the Payment gateway is not able to reach your website to complete the transaction.

1. Verify that your site is actually accessible by visitors. There should not be any htaccess login restriction that would require a user to enter a password to visit your site.
2. Make sure you do NOT have any security plugins that could block the connection to your website.
3. If you have security plugins, disable them and do the checkout process again and verify if the process works.
4. Verify in your Payment gateway account that you do not have specific order return URL specified that is different from the actual website you are tryig to checkout. Any return URL should not be touched and just leave it empty unless advised by the specific payment gateway tutorial we have available. Most of the time, return url is only used by recurring transactions.