Setting Nitro PDF as Default .PDF Viewer

I have Nitro PDF Professional installed on my laptop. I cannot get Vista to recognize it as the default viewer. I've done just about everything else the Nitro support people suggest as well as search the web for others with similar problems. I have Vista Home Premium 64 bit on my machine. If I try running Nitro as the Administrator and then go to a .pdf file in my folder it still asks me to select a software to open the document. When I do, I can open in in Nitro (it then puts the little Nitro icon on the document) but when I close out, the icon disappears and I am back to square one. File association under Control Panel does no good as no .pdf extension shows up on my long list of file extensions.

I installed the program initially under a "Programs from old computer" folder I set up on the laptop. Under my Programs setting, I have this folder as was as the Vista defaults "Program Files" and "Program Files (x86). I've tried copying the Nitro program into these folders as well, but still no luck. Anyone have any ideas on how to fix this problem. It is quite annoying. Thanks.

Hello jimbo2,
Have you tried, Control Panel > Default Programs, and set it from there to open the pictures using Nitro PDF as the default program ?.
Check to see if Nitro PDF is listed there.
Hope this helps, give it a go and post your results, thanks.

I had thought about doing something like this, but I don't really want to assign Nitro PDF as the default program for a file type that I use another program as a default. I think this is just one of those quirks in Vista that was never worked out. Thanks for the suggestion.

I finally figured out how to solve this problem. Here's what I did. When I tried to open the .pdf file, instead of selecting the default program manually, I chose the option to let the computer find a program on the Web. The Microsoft site then gives you several to choose from. I chose Adobe Reader and installed it. Then, I went back in and tried to open up the file again, this time checking the option of letting me choose the default program from my computer. The next screen showed several programs, including both Nitro PDF and Adobe Reader. I chose Nitro and noted that I wanted this to be my default program. I opened a .pdf file, closed everything down and then went to the Default Programs setting on my machine. I chose the Associate a File Type or Protocol With a Program option. I then looked at all the extensions and saw that the .pdf extension now showed up on the list, with Nitro PDF being the current default program.

Apparently, in order to allow you to set a default extension in Vista, you have to have a choice of programs available that can open that particular type of file. All you need is a choice as I never did open Adobe Reader after I installed it.