An error occurred accessing a data source. An entry has been added to the Windows event log of the server. Log ID:5566

ISSUE:

When I access the InfoPath form from the form library as web- browser enabled form, the following error occurred:

Note: this error occurs when you access the forms using host names

SOLUTION:

Please follow the following steps on all my servers:
1.     Click Start, click Run, type regedit, and then click OK.
2.     Locate and then click the following registry subkey: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa
3.     Right-click Lsa, point to New, and then click DWORD Value.
4.     Type DisableLoopbackCheck, and then press ENTER.
5.     Right-click DisableLoopbackCheck, and then click Modify.
6.     In the Value data box, type 1, and then click OK.
7.     Exit Registry Editor.
8.     Restart the computer.