In this article I will give solution of this error message Insufficient Privileges You do not have the level of access necessary to perform the operation you requested. Please contact the owner of the record or your administrator if access is necessary. For more information, see Insufficient Privileges Errors. Click here to return to the previous page. which I got when I clicked on a List button which should open a Visualforce Page.
First lets understand the problem before jumping to the solution.
Problem Statement
I have a custom List button on Account Object. As a System Admin when I click on that button it takes me to VisualForce Page. It works fine for System Admin profile but when I try the same scenarios for profile other than System admin then it take gives me above mentioned error.
Here is what I see when I click on the button as System Admin.

Here is the screenshot of the error which I get when I try the same with other profile.

Solution
In order to fix this Insufficient Privileges issue. You have to follow below steps.
- Go to Profiles from Setup.
- Click on the profile name for which you are getting this error.
- Now scroll down to Enabled Visualforce Page Access section.
- Make sure the Visualforce page which you want to access on the click of the button is listed in Enabled Visualforce Pages.
- Test it again after adding the Visualforce page in Enabled Visualforce Pages.
Here is the screenshot for reference.

We hope you are able to access the Visualforce Page from the List View button. If you have any doubts then let us know in the comment section below.