How long did you wait for PS to come up? I have seen cases on my system where it can take 60 seconds or more before PS becomes visible.
Or start up PS before Edit In and see if LR can pass the document to it, then.
@darkcelt If you are not seeing any error message. Go to Lightroom Preferences > General tab > Prompts select "reset all warning dialogs".
Also try shutting down your computer and reboot.
Thank you everyone for your idea. I did try wait longer to see if the image would load to PS. Still nothing after 5 mins. I also tried with PS already open and still didn't work. Reset the warning dialog, and still nothing... However! You ideas got me thinking and I decided to try to use the edit in function on an image that was not edited in Lightroom... low and behold it came right up in PS. So I went to a new image, did a fast edit, then tried to send to PS and wouldn't work. So for some reason PS is not accepting a Lightroom edit... I do remember a dialog box a while ago regarding if I want to render from lightroom or use original image etc... But I cannot find that reset in the preferences as that is the only thing I can think of... Any ideas where to look for that? Reset warnings didn't bring that box up with I tried the newest send to PS.
It sounds like maybe your camera raw plug-in isn’t installed properly.
Try download ACR 8.7 from here and see if that fixes the situation:
This version is only for PSE-CS6 and PC-CC or PS-CC 2014, so if you are using an older PS then it won’t work.
There is also a minimum OS level of Win 7 or OS X 10.7.
Figured it out.
It actually had to do with an incompatible camera profile (wouldn't load a new one because of the last PS update). Thank you everyone for your help.