Blank emails sent when Visualforce email template called from workflow

I have created visualforce email template for Task Object. Email pops up to the respective user Id when sent through 'Send test and verify merge fields' with content specified in template. And when the same vf email template when called from workflow for Task email pops up but with empty content. Please guide me. Thanks The code below is the Visualforce email template created. On creating workflow for Task object with email alert, email gets popped up but with no content.

      hr < display: block; margin-top: 0.5em; margin-bottom: 0.5em; margin-left: auto; margin-right: auto; border-style: inset; border-width: 1px; border-color: blue; >table < font-family: Times New Roman, sans-serif; border-collapse: collapse; width: 75%; >td, th  
AssignedTo Status 
Subject '' Name '' 
 
Due date RelatedTo 
Phone 9066846020 Email [email protected] 
 
CreatedBy Last ModifiedBy 
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4,073 2 2 gold badges 21 21 silver badges 46 46 bronze badges asked Jan 2, 2018 at 8:45 jayasuriya janarthan jayasuriya janarthan 183 13 13 bronze badges

Does the template refer to a VF component? If yes, check whether the user profile has access to that component.

Commented Jan 2, 2018 at 10:24 Thank you Sagnik. Currently I'm the Admin of this org. , so i have access to every components. Commented Jan 2, 2018 at 10:55

Reduce the size of the problem space to the smallest possible email template; then edit your question with details