And I would think thousands of other people too.
Which "thousands of other people"?? None (Zero, Nil, 0,...) people answering here. Nothing. No agreement. Nothing.
Do you really believe, that this is a common problem to "thousands" of people?? Honestly: I do not.
The main problem is: this happens in your environment. Whatever happens there (i even dont know if you described it correctly), nobody does have your environment. And as it obviously DOES NOT happen to thousands and thousands of different people, we need to debug your installation or PC. And this is quit difficult, If you bring your PC to my home (in Germany), i definately swear(!), I would find out, what is going wrong there, But "remote debugging", without direct access to your hardware, is extremly extremly extremly difficult. I have no idea how to help you, sorry, but this is as it is.
Simply dont use these kind of names (i am pretty sure that there is no need to use filenames with several extensions serialized) and you are Ok. If you are sure, that this the only reason, why not simply changing your file names? By the way: I am pretty, that this is NOT a problem of the extensions and the filenames, it is a problem with any kind of configuration of the software you are running (Wordpress, Joomla or whatever), but for any reason, you do not tell us anything about your software.