'Add/Edit Document’ requires a Windows SharePoint Services-compatible application and Microsoft Internet Explorer 7.0 or greater.

I had this problem using Microsoft Windows 7 Professional 64bit, Microsoft Office 2010, IE 9 and SharePoint Foundation installed. This solution worked for me.

1. Program and Features
2. Select Office 2010
3. Select Change
4. Select Add or Remove Features and press Continue
5. Expand Office Tools and select Microsoft SharePoint Foundation Support. From the drop down,
    'Run From My Computer'. Note: It maybe already selected.
6. Press continue and Reboot system
7. Repeat Steps 1-3
8. Select Repair
9. Reboot System

Disabling Mobile Web Page Access in SharePoint 2010

I recently did some updates to my SharePoint 2010 farm and I had some issue with mobile devices not being able to access my companies website. On mobile phones, users was receiving a "403" and  SharePoint redirected from path http://MyServer/MySite/HomePage.aspx to /_layouts\Mobile\mblwp.aspx.  I searched Google and found SharePoint was using the default ASP.NET Browser Definition file Schema to control whether to redirect or not.  

There is an App_Browsers directory by default in a SharePoint created web application structure (i.e. C:\inetpub\wwwroot\wss\VirtualDirectories\80) which is called compat.browser.

To disable mobile SharePoint views, just find the browsers you want to disable it for and set the value of this flag to “false”. Or do what I did and do a find and replace on:

<capability name="isMobileDevice"                        value="true" />

replace with:

<capability name="isMobileDevice"                        value="false" />

Notes: 
1. You may have to change this in multiple location in compat.browser to allow compatibility different phones and mobile devices.
2. The updates potentially changed compat.browser.