Since the release of the version x.x.x.8 and if you have a previous version installed, some of the page layouts may appear duplicated on the page layout dropdown.
To remove the duplicated files, all the files with "_" (underscore) on the name, you need to follow the following steps:
- Open with SharePoint Designer, the site where you had installed the theme;
- Go to All Files > _catalogs > masterpage;
- Scroll down to where the page layouts are;
- Select all the files with the base theme name and with a underscore on the name;
- Click with the right button;
- Click on "Delete";
- Click "Yes to all" on the next pop-up;
- And files will be deleted.
If appears an error message as "Server error: This item cannot be deleted because i is still referenced by other pages.", is because one or more of the page layouts are still in use.
On this example, the page layout in use is the "TheBoostrapTheme_3_Cols.aspx" and to remove it, we need to:
- Go to SharePoint site;
- Edit the page that have this page layout selected;
- Select the other page layout with the same name;
- Save the page;
- Check it in;
- Publish it.
- Go back to SharePoint Designer and try to remove the file again.
Now, all duplicated page layouts are gone.