The Connection refused error means that it is most likely that an SMTP server is not running on the host that you've specified. Try to enter another address. You can usually get the correct SMTP server address from your email client settings, or see your hosting service's manual / FAQ.
This is a problem that will not allow you to use the SMTP server with the script. Therefore, please turn off the use SMTP Server in Main Config. The script can still send email using the default mail() function provided in the script. The reason for this error is that some SMTP servers require you to log in to the POP server first, before you can use the SMTP server first. (The effect is that users need to read the email before sending) For more information, please see this external website about the POP-before-sending authentication mechanism. http://www.azc.com/htmls/faqs/pop_before_smtp.html
Your SMTP server settings appear to be correct. There is nothing to worry about if you have error 550, the script will resend the email later. You can also try to resend the email manually. If the email status shows as 'error', please wait about 20 minutes before clicking the 'resend' option. The script can also send email without an SMTP server. You can turn off SMTP server by un-checking the 'Use SMTP' option in Main Config, from the Admin.
Question What are the maximum characters allowed in the fields? Answer – The one line text fields are limited to 255 characters – Multi-line text fields and HTML editor are not limited to any size. TIP: When listing the fields in columns, there is a 'Truncate (cut)' functionality which allows you to trim the field to a certain limit when it is displayed on the list. (See Admin -> Ads form -> Ad List for an example, where you can edit the columns on the resume list). Another helpful feature is the string breaking feature which breaks up long continuous sequences of characters. This stops form people inserting content which may break the layout of your site by putting in a space in between the longer sequences. This is set in Main Config, under the 'data cleaning' section. – Radio buttons, check boxes, drop down lists are not limited to how many options they have. – Categories are not limited to how deep they are or how many options they have, but it is always recommended to keep the categories as broad as possible and simple, for usability.
Each order the advertiser makes on the system can only be paid once This is to prevent your advertisers to accidentally pay for the same pixels twice or more. A user who received this error already paid for this order and there is no need to pay again. (The 'invoice' variable issued for each order can only be used once per buyer) If you are testing the script using a PayPal sandbox account, then you are getting this error because you ran a test before where you were using the same invoice id. (For example, this can happen if you make an order, clear your database / re-install, and then make a new test order) OR another script that you were testing had an exactly the same invoice id & item id. To get around this issue, start a new sandbox account for testing the script each time.