How to solve the Warning: Missing required field "updated" in blogger

When you check your blog hosted with Blogger for Google Authorship with Rich snippet testing tool mostly you get two common warning and error messages 'Warning: Missing required field "updated".' and 'Warning: Missing required hCard "author".

Warning: Missing required field "updated"

Note: Before making any changes to the template please take the backup. Link given below will help you.
› Learn how to edit Blogger template?

First Method:
Here we look for first method to correct Authorship markup warnings and error in Blogger template

1. Go to Blogger Dashboard › Select Blog › Click on Template › Proceed › Edit HTML
2. Search for 'hfeed' and 'hentry' one by one and rename all instances those exist in template with 'h-feed' and 'h-entry' respectively. 
3. Save template and now check for authorship markup warnings and errors with Rich Snippet testing tool.

You'll get a smile on your face because no markup warnings and errors will be shown.

Second Method:
Now we move to second method which is slightly difficult from first one.

1. Go to Blogger Dashboard › Select Blog › Click on Template › Proceed › Edit HTML
2. Now press Ctrl+F to find the code timestamp-link   or  published   like below

<a class='timestamp-link' expr:href='data:post.url' rel='bookmark' title='permanent link'><abbr class='published' expr:title='data:post.timestampISO8601'><data:post.timestamp/></abbr></a>

     4. Now care fully change it to the code below

<a class='timestamp-link' expr:href='data:post.url' rel='bookmark' title='permanent link'><abbr class='updated published' expr:title='data:post.timestampISO8601'><data:post.timestamp/></abbr></a>

    5. Now have a smile!

Note: If that code doesn't work please try this: 

<a class='updated' expr:href='data:post.url' rel='bookmark' title='permanent link'><abbr class='updated published' expr:title='data:post.timestampISO8601'><data:post.timestamp/></abbr></a>

You can re check this here Rich Snippet testing tool.