For some reason audition has stopped mixdown in mp3 error comes up saying destination is full although its a massive harddrive with plenty of room yet it will mixdown in wav
Any ideas
Check your temp destinations in Audition Preferences > Media & Disk Cache
See that Audition Audio Disk Cache is set to that big HDD of yours also set a secondary location for extra safety 
Thanks mike
That sorted it the memory on laptop isnt that big explains a lot bit strange that it allows wav which is a larger file never mind it has sorted it thanks again