As nobody seems to have taken up this gauntlet, I'll point you in the right direction - although this is likely to be a baptism of fire (in at the deep end!).
First off, for safety we'll try to rescue anything we can. If your Humax is connected to your home network, disconnect it because we will use a direct one-to-one connection. If it will let you, go into the system settings from the menu button on the RC:
Menu >> Settings >> System >> Internet Setting >> FTP Server >> On
Menu >> Settings >> System >> Internet Setting >> Configure LAN >> Configure IP >> Manual
Menu >> Settings >> System >> Internet Setting >> Configure LAN >> IP Address >> 192.168.1.100
You will need an FTP program on your PC, In my signature panel below click on "Trail Guide" and scroll down to "Stage 1.1 - FTP Access"
Now connect the Humax to your PC directly with a Cat5 cable (network connectors), and using whatever FTP facility you have installed access 192.168.1.100 and see what there is in terms of your old recordings - each one comprises a set of four files .nts, .thm, .hmt, .ts (the main recording file). Copy everything to your PC but note they are huge and will take a long time, also if any of them are 4GB or more in size they have to be copied to an NTFS partition not a FAT32 one. Disconnect the network cable.
What to do now? Probably the easiest to tell you is the HDD test in standard firmware 1.02.27. Visit
THIS PAGE (click) and download HDR-FOX firmware 1.02.27 (make sure you get the right one) and unpack the zip to a USB stick (must be FAT formatted). Install it on your HDR (for instructions see the Wiki).
Now try the disk test:
Menu >> Settings >> System >> Data Storage >> HDD Test
Note that the recordings you FTPed to your PC will
only be playable if copied back to the
original recorder.