John

Glad you're at least running now. If you're still missing a lot of space and your disc appears to have the correct size and chkdsk didn't recover any, you might try the program I referred to earlier (link here: SpaceSniffer) and see if it finds any unusually large files on the disc.

Before that you might just like to check for any space recoved by chckdsk. Recovered space may be in files with names like FILEnnnn.CHK in directories with names like Found.000, Found.001
I think these may normally be hidden, so you may have to right click on C drive in Explorer, Select Tools/Folder Options/View and click the Show Hidden Files and Folders radio button. These files are the orphan pieces of disc that it couldn't assign to known file names. Normally they can be deleted, but you might want to look at them if you think you've lost something important - you may get part of it back.

Mick