InfoPath form library forms cannot be filled out in a Web browser

 InfoPath form library forms cannot be filled out in a Web browser

One or more of the following might be causing this:
The Render form templates that are browser-enabled by users check box in Central Administration is cleared.
The following Windows PowerShell command has been run:
Set-SPInfoPathFormsService -AllowUserFormBrowserRendering $false.
Solution:
Enable browser rendering of user forms by using Central Administration
Verify that the user account that is performing this procedure is a member of the Farm Administrators SharePoint group.
In Central Administration, on the Home page, click General Application Settings.
On the General Application Settings page, in the InfoPath Forms Services section, click Configure InfoPath Forms Services.
On the Configure InfoPath Forms Services page, in the User Browser-enabled Form Templates section, select the Render form templates that are browser-enabled by users check box.
Click OK at the bottom of the page.

Using power shell
Enable browser rendering of user forms by using Windows PowerShell
Verify that you meet the following minimum requirements: See Add-SPShellAdmin.
On the Start menu, click All Programs.
Click Microsoft SharePoint 2010 Products.
Click SharePoint 2010 Management Shell.
At the Windows PowerShell command prompt, type the following command:
Set-SPInfoPathFormsService -AllowUserFormBrowserRendering $true

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