If you have published an InfoPath form to a SharePoint site, chances are that you have created a webpart page and have published it there.
We part pages are great but you lose the left navigation and it can become confusing to some users.

There is however a simple fix that will enable the left nav for your pages. You will need to open up SharePoint Designer to do this.

1. Open SharePoint Designer and navigate to your page
2. Switch to code view and scroll down until approximately line 45.
3. You see the following two lines.
4. Highlight these two lines and delete.
5. Save your page and that’s it!

<asp:Content ContentPlaceHolderId=”PlaceHolderLeftNavBar” runat=”server”></asp:Content>
<asp:Content ContentPlaceHolderId=”PlaceHolderNavSpacer” runat=”server”></asp:Content>
It will look similar to the image below: