i have 3 plugins that aren't loading, Admin Radar, Backpacks and Spawnmini. i have removed and downloaded lastest versions and installed. tried reloading and says there's no plugin named "admin radar" etc.. 
have restarted server many times. all other plugins work fine, just these 3 are "unloaded",
what else can i try? cheers

Please check your logs for errors. Also, with commands, you would use the file name with the EXACt casing. The file names also need to have no spaces or symbols and should match their main class.

For any help with errors otherwise, please use the support sections for each plugin.

Try     o.reload AdminRadar       what does it say?

Make sure the files in the folder "plugins" have the exact same name and extension as you downloaded them, capital letters too!  

For example for Admin Radar your folder should look like:

server folder/oxide/plugins/AdminRadar.cs 

Then you run the command in the console

oxide.reload AdminRadar (make sure you do not write ".cs" here)