Windows7 Opentype Fonts Issue

I have had this dell pc for a year. I had a lot of opentype fonts installed on here as I am a graphic designer. All of a sudden I notice none of my OTF files are in my photoshop list..I checked the windows/fonts folder and not there either. I try installing new OTF files and it says "not a valid font file"

Here is the kicker..I converted my OTF files to Truetype and when I install them windows says its already installed, but you look at the list and nothing there. I have tried everything, read all the forums..here is what I have done

I am logged on as admin. I removed my kids account so there is only one account (admin account)
I updated my graphics card (read that can be an issue)
I have changed the UAC to never notify
When I click on the font properties there is NO box that says unblock
I sent the file to a friend, they installed fine, so its not a corrupt file.
I have Restored Default Windows 7 File Extension Type Associations (otf - Open Type Font file. The default program is Windows Font Viewer.)
I read it could be an adobe issue and was instructed to Open the registry editor (regedit)
Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management
Add a new REG_DWORD entry called SessionImageSize with a value (decimal) of 20

None of these have worked.

I just don't understand how they were installed and working fine and now they are not and I cant even add new OTF files.

Anyone have another suggestion?
Dell wants me to pay 240 bucks for a software warranty to tell me how to fix it.

Windows 7 Professional 64 bit
Dell Inspiron 560s
NVIDIA GeForce 310

Thank you to anyone who has a suggestion...im at my wits end and I really need these fonts for design.

http://img545.imageshack.us/img545/9093/73796179.jpg

 

Thank you very much for your quick response.

When I open the c/windows/fonts it does not display the OTF fonts at all. Only when I converted them to TTF and tried to install them, I got the message that the font is already installed. If you look in the directory you cannot physically see that font in the list.

I also started in safe mode and got the same result. No opentype Fonts in the list.
So I cannot check the color or even right click to get properties...its not physically there. Although I know it is there..I have used them on this pc a hundred times and like I said above when I try to install the converted file, Windows says its already there..do you want to replace? Also while in safe mode I tried to install a new OTF and received the same "not a valid font file" message.

 

Hi

I am having the same issue and tried all the suggested fix as well but I cannot seem to be able to install OTF fonts on my Windows 7. This is driving me nuts.

Did you manage to find a solution in the end? Thanks.