How to Resolve BCS (SharePoint 2010) Error "Login failed for user 'NT AUTHORITY\ANONYMOUS LOGON"

Here are the steps to resolve BCS (SharePoint 2010) Error "Login failed for user 'NT AUTHORITY\ANONYMOUS LOGON":
1) Open Powershell (Run as Administrator) and type the following lines:

$bdc = Get-SPServiceApplication | where {$_ -match "Business Data Connectivity Services"}
$bdc.RevertToSelfAllowed = $true
$bdc.Update();

NOTE - That your BCS Service Application should match the name as above. Else change it to what your BCS Service application is called (the way you find out is by going to Central Admin > Application Management > Manage Service Applications (and look for BCS Service App name)

Once above is done, Open the External Content Type in SharePoint Designer 2010 and Click on Edit Connection Properties:





Once the Edit Connection Properties dialog opens, ensure that you have selected the "BDC Identity" value for the Authentication Mode property

Go Back to the ECT Read screen in your SharePoint site and hold your Ctrl key and click the refresh button on your browser. EUREKA! The error "Login failed for user 'NT AUTHORITY\ANONYMOUS LOGON" should now get resolved and you should see results displayed from yor LoB