Tutorial: Moving Old Saved Game Ships To Modern KSP

[Titler]

Hello all; this will be a basic guide as to how I managed to save my ancient Kerbals from doomed old saves, and bring them back to life again in my modern game. If I'm missing something, I hope others will add their knowledge below. I make no guarantee it will work for ALL previous saves; but this is how I managed to retrieve my own older vehicles, and I hope it will aid some of you to do the same as I wasn't able to find much information of how to do so, and had to work it out step by step myself!

STEP 1: PREPARATION

You will need the "persistent.sfs" file from your old save. Make a copy of this somewhere, so you don't accidentally ruin it. We will be working from the copy only.

Also make sure to make up your current save file somewhere safe, so you don't lose it. They can be found at the following location;

Install location\Kerbal Space Program\saves\

Copy the lot somewhere too, so you don't lose your current vehicle designs.

Now, download this simple editing tool. It can be run from anywhere, so don't worry about where it goes for now.

 

STEP 2: FIRST STEPS IN EDITING

You do not need to shut KSP down, but the game can't have the save you're moving too open, so close it and go to the title screen. You can re-open it later to see if your changes stick.

Run the editor. Then click "File" and select "Open".  Point it at the copy of your OLD "persistent.sfs". This is where we shall be taking the data from. Then click "File" and "Open" again, and select the current saved game's " "persistent.sfs" file. You should then have two tabs open, which looks a bit like this:

Notice I'm retrieving a lot of vessels and kerbals from all the way back in version 0.20.2.  And it works, I promise!

Expand the tab that says "FLIGHTSTATE"; most of what we need to get at is in there.

Right click the line that says "UT = xxxx", then hold down SHIFT + Right Click on the very last VESSEL in the list, and select "Copy".  You should have selected all your old ships, and a lot of Kerbals. Flags are classed as "VESSEL"s so these should be moved too.

Now swab to the new save tab, and delete the "UT" line there. Then right click on the Flightstate line, and "Paste" to add the old values in.

If you are moving to an new saved state that has other vehicles active, right click on the "activeVessel = x" in the new save, select "Edit", and change the value from to (New + Old). In my case I had none active in the new, so left "activeVessel" as 8, the old value.

If you want to take things slowly, move a single "VESSEL" first that doesn't have a Kerbal in it, and is remotely controlled somehow; once done, in the editor still, make sure the New file tab is highlighted, then click "File" and then "Save". Point the editor back at the new save file and over-write it. You did back it up first though, yes? Now we can start KSP or load it from the title screen and see if our changes have stuck.

There are two issues that can cause problems here. The first is that without the Universal Time matching the old save, KSP seemed to get confused as to where ships etc are supposed to be, as planets etc aren't where they should be. This I believe is what the UT line does, so I copied it across. If you have other ships active, and thus are trying to move to a save in a different time frame, this may prove an issue. Please let me know in comments.

Secondly ships with multiple crew and multiple sub-components (like space stations or two docked ships) loaded, but weren't able to be Flown from the Space Centre. There are two ways to fix that. The easy way, and the hard;

THE EASY WAY:

Under the editor, re-copy from the old file only the Kerbals listed, and paste them into the new "ROSTER" line on the new save.

This meant they were duplicated in two places in the new save, but it didn't seem to cause any trouble so I just ignored it. You should now be able to fly your old craft with the old crew back aboard.

THE HARD WAY:

Maybe you don't want to try and retrieve the old crew, because it means you end up with duplicate Jebs all over the place. Or maybe the above hasn't worked for you for some reason?  There is a way to re-generate a fresh crew in game though. And that is... simply fly back to it and get close enough that you can swap with the [ and ] keys between your two ships, and the missing crew will be replaced with new ones. My Munbase, abandoned for nearly 3 years, was visible on radar but couldn't be accessed at first, so I sent some brave Kerbals out to see if aliens had eaten them, or they'd eaten all the snacks since I was last able to load them up and had starved to death; once within range, the lights spookily came back on and fresh faces could be seen peering out the windows...

Good job Sherbald Kerman was already bald, or all his hair may have fallen out due to shock! To avoid this issue in the future, I plan to have at least one automated control system aboard my space stations.

MY SHIPS WONT LOAD! IT SAYS I HAVE MISSING PARTS!

One of the problems with saving old ships is that they may have parts aboard that no longer work, or aren't installed any more. They can be retrieved, but it requires much longer fiddling.  Bear in mind the following condition must be met; The ship can't use the missing part as a connection between two other parts. If it does (say you have a seat stuck on top of that part) it just won't load if it's removed, as far as I can tell.  Correct me in comments below if I'm wrong! On the above space station, I had some old MapSat scanners mounted radially however, and I was able to fix these. How?

EDITING IN FLIGHT VEHICLES:

Firstly we need to identify which vehicles might have the error; when you attempt to load the game itself, it should tell you which active vehicles have missing parts. And when we try and open them in VAB it should warn us again.

Under the "FLIGHTSTATUS" lines in our New Save, find the VESSEL, in this case Munbase, and double click it. You will now get a full list of parts aboard like below;

 

Scroll down until you find the one preventing it from loading, in this case "ISA.GPS" (which is Map Sat, but remember it tells you when it tries to load the name of the broken part) and Delete it.  Save here, then resave the entire "Persistent.sfs" file again.

EDITING VAB DESIGNS.

In the editor, you can open the ".CRAFT" files directly, and remove the broken parts from the list, just like we did above for the station. However because the old file format might carry across, you may still get this error when you attempt to load in KSP:

You can "Attempt To Load Anyway"; the vehicle should appear in the background, and even though you get the error here a second time, just click "Cancel". Now you just need to do one small edit, even just take apart and put back together the vehicle, and then re-save over the old version to correctly update it and use it from then on.

If it doesn't load a second time, and only one for me did not because I made a slight error editing the CRAFT file by hand earlier, you won't be able to load it in KSP at all, and it won't appear no matter how often you click Attempt To Load. The way around this is to create a blank CRAFT file in KSP, then using the editor, copy all the parts data etc back across from the old file, then re-open in KSP and see if you can save it that way. But hopefully you won't need to try!

 

And that is how I got all my old space stations from v0.20.2 back into the modern game! I hope you've found this guide helpful in saving your own wee green wonders.