Hello,
Thank you for contacting us about Adding Products in PrestaShop. I recommend enabling error reporting in PrestaShop 1.6, which can provide detailed clues into problems.
We are happy to help, but will need additional information to help troubleshoot further.
When did this begin happening?
Was it working before?
What were you working on when it started?
Let us know if you have any further questions.
Thank you,
John-Paul