How to figure out which mod(s) are causing problems in your install

[linuxgurugamer]

There is a general technique which can be used to narrow down a problem.  It's used quite frequently by players in KSP to find mods which are acting up.

This is both a description of the technique, and the videos are showing how I used it on two lives streams (5/10/2020 & 5/21/2020) when a problem appeared in a new, heavily modded game.

The simple technique is as follows.  While the discussion will be aimed at a Windows system, it applies equally well on a Mac or Linux:

Definitions

• KSPDIR - Main KSP directory, where the exe file is

Steps

1. Most important, copy the ENTIRE KSPDIR into a new location.  You can use this new copy to do your testing, or use the original (if playing via Steam) and use the copy as a full backup.
2. Create a new folder in KSPDIR, call it:  DisabledMods
3. create another folder called: GoodMods.  This is where mods determined to not have an impact on the problem will be moved to.
4. Open the GoodMods folder, move it to the left.
5. Open DisabledMods and move it to the middle
6. Open the GameData folder, move it to the right side
7. You should have three folders open, GoodMods on the left, DisabledMods in the middle and GameData on the right
8. Select half of the folders in the GameData, but do NOT include the Squad folder.  You can include the SquadExtensions if you like
   1. Note:  Some mods have dependencies, if you remove a dependency, the mods won't work.  Of note is that there will most likely be some folders in the GameData which begin with 000_ or 001_.  These folders are usually the dependencies.  Of specific note are the following. which are dependencies of most of my mods:
      1. 000_ClickThroughBlocker
      2. 000_ToolbarControl
9. Move the selected folders to the left, into the DisabledMods folder
10. Test the game, and see if the problem still exists
11. Exit the game
12. If the problem still exists, then move all the folders in the DisabledMods folder into the GoodMods folder
13. If the problem does NOT exist:
    1. then move all the folders (except Squad) in the GameData folder into the GoodMods folder. Then, move all the folders in the DisabledMods folder back into the GameData folder
    2. Test the game again, to verify that the problem reappears.This is important, because sometimes a problem is caused by two mods interacting with each other in unexpected ways.

Go back to step 8 and test again.  Keep repeating the cycle until you've identified the bad mod.

So, assuming you have a simple problem and 100 mods, this will take no more than 7 repetitions before you isolate the bad mod

Sometimes, however, it pays to make an educated guess to shorten the process.  In the videos below, I use playing in an about 200 mod folder, and given how long it takes to start the game, I tried to shorten the process.  An educated guess is thinking about what's going on, and trying to first move mods which would logically have no relation to the problem first.  For example, parts-heavy mods usually are safe to move out.  A few notable are:  KWRocketry, SpaceY and SpaceY Expanded, RLA, SXT, etc.  If in doubt, look in the mod directory for any file which ends in .dll.  Quite often DLLs will be inside a folder called Plugins, sometimes they will be in the top directory of the mod, and very rarely somewhere else.  Issues are usually caused by code in the DLLs, so if you have a parts mod with a dll file, you may want to consider initially leaving it.  For example, the SXT mod has a DLL called ModuleBounce.dll, which is used for the airbag part.  This is where the educated guess comes from;  in this case I know that ModuleBounce.dll is only used by one part, and that part hadn't been used in the problem. (actually, SXT wasn't installed in the game, but you get the idea)

So, a modified set of steps may include:

1. Most important, copy the ENTIRE KSPDIR into a new location.  You can use this new copy to do your testing, or use the original (if playing via Steam) and use the copy as a full backup.
2. Create a new folder in KSPDIR, call it:  DisabledMods
3. create another folder called: GoodMods.  This is where mods determined to not have an impact on the problem will be moved to.
4. Open the GoodMods folder, move it to the left.
5. Open DisabledMods and move it to the middle
6. Open the GameData folder, move it to the right side
7. You should have three folders open, GoodMods on the left, DisabledMods in the middle and GameData on the right
8. Move the mods which, in your opinion, are not related to the issue to the DisabledMods .  Pay attention to the larger mods, such as big parts mods.  Moving them out will reduce the load time of the game, very important if your system is not lightning fast.
9. Run your test.  If the problem still occurs, then you have just eliminated some possibilities and speeded up the test cycle.  Move the folders in the DisabledMods into the GoodMods
10. From this point on, it mostly the same.
11. Select half of the folders in the GameData, but do NOT include the Squad folder.  You can include the SquadExtensions if you like
    1. Note:  Some mods have dependencies, if you remove a dependency, the mods won't work.  Of note is that there will most likely be some folders in the GameData which begin with 000_ or 001_.  These folders are usually the dependencies.  Of specific note are the following. which are dependencies of most of my mods:
       1. 000_ClickThroughBlocker
       2. 000_ToolbarControl
12. Move the selected folders to the left, into the DisabledMods folder
13. Test the game, and see if the problem still exists
14. Exit the game
15. If the problem still exists, then move all the folders in the DisabledMods folder into the GoodMods folder
16. If the problem does NOT exist:
    1. then move all the folders (except Squad) in the GameData folder into the GoodMods folder. Then, move all the folders in the DisabledMods folder back into the GameData folder
    2. Test the game again, to verify that the problem reappears.This is important, because sometimes a problem is caused by two mods interacting with each other in unexpected ways.

 

Go back to step 11 and test again.  Keep repeating the cycle until you've identified the bad mod.

==========

Real Life Example

Over the past two nights, I've engaged in a common situation where two mods were interacting badly and causing strange errors in the game.  To make it worse, I had no idea which mod(s) were the problem, and I had about 200 mods installed.

I've taken the stream videos and edited out some superfluous parts, and am presenting them here.  They ARE long, but both show the techniques used by many people to isolate and figure out which mods are causing problems.

This first video starts when I am starting the troubleshooting session.  There are 200 mods installed, no idea which mods are the problem:

 

This second video is after I've figured out the first mod, and am starting to look for the second mod which was an issue:

 

 

Edited May 13, 2020 by linuxgurugamer

[linuxgurugamer]

Reserved

[Gargamel]

Moved to Tutorials.    This will come in handy!