I bought the 860 from Amazon about three weeks ago and am now in the process of sending it back due to the dreaded C13:00 error message.
The problems other people have had with this machine seem more to do with problems using the DVD drive. But this is happening when I'm trying to record to the HDD- not all the time but roughly about once in every 5 five record attempts.
If you look at US forums you'll see this was a big problem with earlier Sony HDD recorders.
Also the pause live TV function isn't working (again a problem other people have had).
Has anyone got any advice about whether it's worth trying to reformat the hard disk?
I'm tempted to simply take advantage of Amazon's 30 day refund/replacement policy and get a new machine.
But other than that (although it's a big "that") it seems to be a good machine- easy to set up and use. The inability to record series is pain though- although I understand that's a broadcasting problem.

Don't Bother With A Replacement..... Go For A Refund And Go For Anything But Sony..... Got In To Work This Morning And Someone In The Office Has Got The Very Same Issue On A Brand New Machine Not 30 Mins Out Of The Box.........

if I've Learnt Anything From These Last Few Days Is Never Ever Buy Sony Again.

Yeah- I get your point mate- but Amazon (with typical efficiency in my experience) are getting a replacement out to me today.
As I said in my orginal post, if this is a glitch specific to this machine I'll be very happy with the replacement!

I always tend towards Sony products (I'm incredibly pleased with my new Bravia) and- assuming this isn't a problem with my new machine- it won't put me off

As someone pointed out elsewhere.... forums do tend to attract people with duff machinery..... it just seems odd that SONY seem to be having a really bad run of luck at the moment... what with PS3 delays, battery recall all the 710 and 910 problems....... also it seems SONY are having trouble with a minidisc player destined for the broadcast use.... anyway good luck! Please get back and let you know how you get on.......

Ive just posted in another thread about this error message.

I got the Sony RDR-HXD1065S and had this a month when I got the C1300 message today when trying to record to the HDD. Said Disk dirty.

Only had the machine a month so looks like I will be taking this back!!!

I got my 860 when they were launched around last Aug-Sept time and have to say it been fantastic and ultra reliable. Never had a problem with it and it really does get a lot of hammer. I'd be knackered without it! I'm not sure how to get it to play Divx files but other than that it's the business.

I'd totally recommend Sony to anyone from my experience.