Hi Ravikash,
Conflicts with the default program settings is one of the possible reasons why you are only having white plain icons on your .DOCX files. To resolve this, I would recommend that you perform a Repair Office from the Control Panel. You can follow the steps in this link.
Should you need further assistance, don't hesitate to get back to us.
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I performed the repair and also set word as default program but did not help. Please provide any alternative solution.