Responsive HTML5 layout generates first time only; must create a new layout to generate content thereafter

I have RoboHelp 2017 installed, and it's been working normally with my Responsive HTML5 layout until yesterday. Yesterday, I attempted to apply my master page with a footer to the output layout and generate the help. It generated normally, but when I tried to regenerate the help, it would show the loading icons in the TOC and content frames. I cleared the option to apply the master page, but that didn't fix the problem. Now, I have to generate the help once, and if I need to regenerate it, the only way to get it to work is to create a new output with the defaults selected, and try that once. Each layout works for the first help generation only. After that, a new output is required. Has anyone seen this issue?