Exporting Shared parameters

I did this yesterday....I had some shared parameters I added a while back to some titleblock fields and they were not in my shared parameter file. So I opened the titlebloc, clicked on the label, clicked the Select Parameters button, clicked modify and finally lcicked the Export button. The parameter was placed under an Exported Parameters group. I then used these where I needed and once I was done, I removed them from the shared param. file.

Well, today I realised I needed to re-use one of those parameter sone more time, so after cursing myslef for being so quick to delete these temporary shared parameters, I thought I'd repeat the procedure. But, for some weird reason, now the Export button is greyed out! Is there a one-time limit for using this function on a parameter?!

Well, I figured that you can just do a copy/pase of a label and the shared parameter will come in....much faster than exporting anyway.