eBay can return this error and cause your listing to fail for two main reasons.
1) Account Restrictions
In a situation where eBay may have placed restrictions on your account, you won't be able to create new listings and this error will be given. In such a case, look out for a message from eBay in your eBay account or seller dashboard which will detail what the restriction is and how you can fix it. These resctrictions may also only be placed on certain product types or categories and will be lifted once you have provided certain information.
Your account may also have restrictions placed on it for the following reasons:
See the links below for further information on eBay seller limits:
2) Violations of a listing policy
For every listing you try to create on eBay, eBay checks the information submitted (in the title and description especially) to ensure it complies with its rules and policies. Several issues that have to do with illegal/banned products, profanity, fee avoidance, links, email addresses, etc are being checked for. The item will not be listed if eBay believes you have violated any of the rules or policies.
How to resolve it
It can be a bit difficult resolving this issue since eBay does not provide the exact reason the message has been given or the exact rule or policy you have violated. However, the following can help point you in the right direction:
1. Familiarize yourself with eBay's overview on rules for listing.
2. Pay particular attention to your title and description for phrases and words that may be in violation of their policy such as profane words, links, email addresses, website addresses, phone numbers etc. See what to avoid in your title and description here.
The following are examples of terms found in the title or description that can cause eBay to give this error:
3. Also, note that eBay regularly changes its rules and policies. Looking out for any new updates to the rules and policies will be worth it.
Contact support at firstname.lastname@example.org if the problem persists.