The only way that your posts_default_body could get overwritten with the posts_body (converted to HTML) is if you ran the following chunk of code:
WARNING, do NOT execute the below code, it will make all of your posts HTML
Code
UPDATE ubbt_POSTS
SET POST_DEFAULT_BODY = replace(POST_BODY,'http://EXAMPLE.com','https://EXAMPLE.com')
WARNING, the above MySQL Query is purposfully incorrect as an example, do not EVER execute the above query.

While attempting to run:
WARNING, managing the UBB.threads database is not only not recommended, it is not supported
Code
UPDATE ubbt_POSTS
SET POST_DEFAULT_BODY = replace(POST_DEFAULT_BODY,'http://EXAMPLE.com','https://EXAMPLE.com')

WARNING, if you are prepared to manage your database directly, despite warnings, please ensure that you create a backup before executing any queries.


You SHOULD be able to just use the Active Text (text replace) feature in the control panel to change data coming from the database to the browser (such as URLs, linking to affiliate products, etc).

I am a Web Development Contractor, I do not work for UBBCentral. I have provided free User to User Support since the beginning of these support forums.
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