If you are running WordPress in debug mode or you have PHP set to display all notices and warnings, you may get an error when saving a post or a page with WP-Members 2.8.2. This is the result of a typo that slipped through quality control before this version was released.
The error has already been corrected in the 2.8.3 project package, but since that is not out yet, you can easily apply the fix as follows:
In the /wp-members/ folder, look at the file /admin/post.php. At line 94 it will read as follows:
if( !current_user_can( 'edit_post' ) ) return;
Change it to this:
if( !current_user_can( 'edit_posts' ) ) return;
The difference is an “s” in “edit_posts”. There is no “edit_post” capability, which is what throws the error.
Incidentally, you should probably not be running WordPress in debug mode on a production site anyway. But if you are, this fix will clean up the issue.