Originally Posted by unitron
51 and 52 basically force the partition swap, which may switch you to a newer version of the operating system if for some reason it's been sitting there on the alternate partitions but the switchover wasn't made automatically. Otherwise it may actually switch you back to the previous version of the OS.
Whatever your problem is, this probably won't solve it, but the partitions where your shows are recorded shouldn't remain unmessed with.
If you want to try fixing things with a KS, try KS 58.
KS52 will never result in you winding up with an older or newer version of the OS. It takes the OS version that you are currently running, installs it and related data, onto the alternate set of partitions, and switches them to be the active ones, upon the next boot/reboot. Before and after this process, the TiVo runs the full battery of integrity checks and garbage cleanups on both the current set, and the alternate set. Whatever set is not in use, will always be the "alternate set". The recordings stay right where they are, and the related structures are checked for integrity. Unless the drive has physical defects, a KS52 should never cause loss of recordings.
The ONLY way switching which set is active could cause an OS version change, is if you manually did so, using a 3rd-party tool, like WinMFS, or manually changed the configuration using a disk/hex editor, and did so without running KS52 first. Running it first prevents an OS mismatch from corrupting databases, and/or the OS from being unable to work with the databases.
For whatever reason, every TiVo I had ever owned (before Roamio), was rendered unrecoverable, more than once, caught in a GSOD reboot-loop, by use of KS57 and/or KS58. Yet, none ever suffered the same fate by using KS52, even though it is far more through and aggressive in operation.
Since the last thing TiVo ever wants is a software update borking a TiVo, and KS52 emulates a software update (uses the same routines and mechanisms), you are safest using KS52, even if KS 57 and/or KS58 sounds like exactly what you want. You will still get all (good things) that KS 57/58 has to offer.
There have been reports of TiVos with bad sectors in the alternate partitions going belly-up. But, you have to consider that the day was coming anyway, if the drive was developing bad sectors. I made it a habit to run KS52 every 6 months, on units that ceased receiving updates, or went longer than 6 months without one. This helps balance the wear and tear on the drive.
One thing that is finally fixed with the Roamio, is that I can't even force a KS57/58 to bork a Roamio. I've tried very hard at it. KS52 is no longer functional on Roamios, leaving KS57&58 as the only repair and cleanup kickstarts available.
On any TiVo before the Roamio, I'd never even consider running KS57/58, or advise others to do so, if there was anything on the TiVo that was important. It's a coin toss, if 57/58 will help, or put you into a boot loop, requiring a drive reimage, and loss of all recordings. KS54 once borked a TiVo HD for me. But, that could have been a complete fluke, which the lack of reports about such a thing happening to anybody else, seems to point towards.
The usual 3 people can now chime in that they have never had a kickstart cause any ill effects.