There have been significant improvements to the coding since v7.5.5 was released on February 10th, 2010; several of which have to do with web standards changing over the years, new functionality, support for newer versions of PHP (generally compatability), etc.

It's basic evolution of web technology, such as how UBB.threads will currently not run under PHP7, PHP5.4 being required to run v7.5.7+, PHP 5.3 required to run UBB.threads v7.5.4+, etc.

As you said, nothing has changed within your UBB.threads forum, which leaves server side changes.

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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