Docking wont kick in.

[kizentheslayer]

I was half way to Duna and when i tried to dock my lander the magnet kicked in but it would never dock and it stayed in with the two ports appearing to clip. I know the magnet has started because i can't back off on the lander with the rcs. I clicked decouple node on the docking port to separate the two ships before attempting to dock.

[LABHOUSE]

Well even if they are not docked, if you cannot rcs away then it might be safe to fly off to kerbin like that.

[kizentheslayer]

Well even if they are not docked, if you cannot rcs away then it might be safe to fly off to kerbin like that.

Do you mean not be safe? cause it acts like a deadweight. This has happened several times before.

[LABHOUSE]

Well if you do not need the lander just Eva crew out and go home, but if the lander still has some fuel do what I said earlier.

[kizentheslayer]

Well if you do not need the lander just Eva crew out and go home, but if the lander still has some fuel do what I said earlier.

Im trying to figure out how to fix the docking problem. I can get home fine its just I don't want to waste a hour on a mission only for KSP to crap out the docking. It has happened on multiple ships/stations/probes etc, but seemingly at random reloading at the problem time doesn't help.

[MisterFister]

There were a handful of threads from last year discussing this, such as http://forum.kerbalspaceprogram.com/threads/35777-Can-t-Undock-Bug-How-To-Fix and http://forum.kerbalspaceprogram.com/threads/78863-FIX-Dock-Undocking-Bug-in-0-23-5?p=1136991&viewfull=1#post1136991. Unfortunately, it might be an irrecoverable error that would require manually editing your savefile, or possibly restarting your save.

The issue comes from how the savefile treats docked vessels and VAB-assembled vessels differently. Docking ports all have a UID (universal identifier) that points to the UID of the other port that it's attached to. If one of the ports points properly to the second port, but the second port's pointer gets corrupted so some number that the game cannot interpret, you have to go digging through the savefile to manually fix it. This is not impossible, but it can be very tedious, and if you mess it up the entire save will become permanently unplayable. (So make a backup before attempting.)

What always frustrated me is that no one seems to know what causes it. I seem to recall discussion that Squad was aware of the bug but had no idea what caused it. Crude troubleshooting attempts seem to suggest that it might be influenced by craft that had a lot of spent launch stages (staging events during launch) before undocking and then redocking, Apollo

Edited November 27, 2014 by MisterFister

[kizentheslayer]

Crude troubleshooting attempts seem to suggest that it might be influenced by craft that had a lot of spent launch stages (staging events during launch) before undocking and then redocking, Apollo

That might be it. It is a double Asparagus ship.