Contextual Filters using Taxonomy Works in Preview but not on Page

Drupal is an intensely complex software environment.

I wouldn't dane to try to actually debug such a problem long distance.

Meanwhile, yes, disabling a View is a good way to "get rid of one" temporarily. Disabling all but one View and getting that one View to work is a good diagnostic thought process.

Thankfully, Views can also be exported and imported readily. Use the export feature to make backups of your View as you make changes, so that you can version rollback or version rollforward if necessary.

If you are using a contextual filter in your View, the way in which it is defined could be the problem, when combined with other aspects of a complex view.

For all things Drupal, I keep a plain vanilla Bartik Drupal install handy in which to build proof of concept implementations of things before trying to implement them in an actual project. This helps to differentiate site specific problems from generalized feature implementation problems.

You may want to create a test version of a View concept in a plain Bartik site, with any necessary custom content types defined and so on, and try to implement it there and they re-implement the View in your actual development site.

As the years go by, as a software scientist, I have more and more concluded that Drupal is a tool for programmers who are able and willing to solve the complex problems that arise. You are not alone in your plight.

I too had some frustrating drupal problems the other week that required extraordinary measures to diagnose and debug, including resorting to inserting drupalmessage calls into code and stepping through PHP in a debugger.

Also, if you are working on a Drupal project, it helps to make extremely frequent database and code backups, dated and numbered sequentially, so that you can rollback if necessary, or to be able to install a previous version onto a test URL temporarily for diagnosis. I keep both a local XAMPP setup with PHP debugger capabilities, and a cloud based LAMP stack onto which I can create unlimited urls for development and testing. Both are a necessary investment for serious Drupal efforts.

I'm assuming there is nothing special about your taxonomy vocabulary, it just has terms "music", "viewpoints", etc.

Create a new view, showing content, of type all, sorted as you wish, and create a page.

Give the page a path of categories/%. The first part of the path is required for a view page to work. It can be anything you want, but it needs to be static. The second, %, is the dynamic argument that will determine which taxonomy filter is applied. This is possibly why your existing view does not work, you can't have just a single dynamic argument as the path.

Under "advanced", add a contextual filter with "Content: Has taxonomy term id".

Now you want to be able to use the taxonomy term name as the filter, not the id number. So check "specify validation criteria".

Choose "Taxonomy term" as the validator.
Check the vocabulary you wish to filter by.
Choose "Term name converted to term ID" as the filter.
Check "Transform dashes in URL..."

Test using the preview with an argument of "music". The argument is case sensitive.

OK? Save the view.

Go to /categories/music

What you see there should match the preview.

To get the term name as the page title, check "Override title" in the argument settings, and use %2 which should grab the term name from the converted second argument.

Now, if you really don't want a static argument preceding your term name in the URL, there is a way to achieve that using Entity View Attachment module, attaching a view to the taxonomy term page (rather than using a view page), and using Pathauto to rewrite the term page path. But first verify that an ordinary view page works as above.

One thing about both View Reference and EVA is that you can have your page paths without the "articles" prefix and still pass the taxonomy term in as the view argument.

In EVA you use token replacement in the arguments setup, in View Reference you manually specify the term when you reference the view. I'd go with EVA first.