Plugins not showing up on dashboard

I have been trying for several days to figure out why the plugins that I have uploaded to my server and are in the correct folder the correct way do not show up on my dashboard plugin page. I have also had a tech at my server also check it and he cannot find anything wrong with it. All the plugins that I uploaded to the server are supposed to work with 2.5. Akismet and Hello Dolly both show up and when I look in the file on the server the rest are there in the same format. I have tried everything I can think of to do including changing security to allow more access. Help please.