I have a 35Mhz 12-20DR Rx, which was last used in November 09. Up until and including then, each session was logged ok on the memory card. I used the rx again yesterday and although each session has created a new .NAV file, I can not access the data from the files I need to - the ground test and the 2 flights. There are 11 files that have been created, mostly small files of a few hundred kb from short sessions while adjusting or checking something. Four of the files have the following problem, and three of them are the ones I actually need to get at, three of them are approx 1.3MB the other which I don't need is a few hundred kb like all the others that do work.

If I try to copy the 4 problem files from the SD card to the hard disk I get an error message saying the files can't be copied as they or the directory are corrupted and unreadable. If I try to open them in Nav View I don't get an error message but I don't get any data either, it all remains blank. All the other 7 files work no problem. I put the card back into the rx and cycled it a few times to make files 12 to 17 on the card, and the computer can copy them and Nav View can read them fine. Any ideas why the four files from yesterday have a problem, and any idea if I can do anything to recover them? All the files say they were created on 1 January 2098.

thanks

Harry