Hi @Rajesh Pathak ,
Have tried correcting the same using MFCMapi (The Structure though is different from what is depicted in the same thread earlier
Is it the thread you mentioned-- Favorite contacts disappear on Outlook restart? If so, what are the properties that you have deleted? Based on my tests, here is the location of my Qucik Contact list, I think there may be some differences between different versions, if you haven't deleted it, it's suggested to try it and restart your Outlook to test(Remember to work on online mode).
If you have deleted them and the issue still exists, in order to avoid the interference of corrupted Outlook profile, it's also suggested to create a new Outlook profile and readd your account to test(Control Panel>Mail>Show profiles>Add>type a new profile name>readd your account)
Hope that would be helpful to you.
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