I had exactly the same problem a few days ago, MadameX, except it was after a render crash.

First of all, make sure that your original Poser.xrc file is named correctly (you saved the original version under another name, right?)

If that does not fix it, then try a re-install of the latest SR for your version of Poser. Just install it over the top of your current Poser program, and keep your current preferences. Nothing in your Poser Runtime will be deleted.

If you have Poser Pro, make sure to install the separate Queue Manager SR1 update as well.

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)