FTB Infinity Evolved will not start (Potentially invalid instance)

[torbeneims]

After playing for a while, I got an error message stating that my instance was "potentially invalid" and asking if I would like to proceed. At first, I did not but as restarts wouldn't fix the message I continued anyway without any success. The game crashes before launching. Many reboots and reinstalls of the pack, FTB and Overwolf have brought it to the point where I can play without LogisticsPipes. After starting, the game will crash, delete the mod and start normally the next time. Since the server (and world) are running with LogisticsPipes, I would like to keep it that way and resume normally. Note that it does not show the "potentially invalid instance" when crashing and deleting LogisticsPipes, making it four states I can get the game into.

1. "Potentially invalid instance"
   What is this? The launcher shows the warning "Potentially invalid instance - Your instance appears to have duplicate mods orinvalid scripts. It is highly recommended that you re-install your instance. Do you want to abort launching? - Launch or Abort". The game crashes after a split second. You can find the crash report "crash-2022-04-16_19.13.55-client.txt" attached.
   When does this occur? After starting the instance like on any other day OR after a fresh installation with the exception of replacing the mods with the mods from the (running) server installation.
   Is the installation modied? Yes and No. We changed "Crafting Only" in the Avaritia Config from true to false, pasted "tconstruct-moltencasts.zs" (regarding Tinker's Construct) into modpack/normal/scripts and added NodalMechanics-1.7-1.0-7.jar. The recreated server instance does not contain any of these changes. The server is running with the exact same mods (with and without Nodal Mechanics) as well as with or without those modification.
2. Crashing clean installation
   What is this? The launcher launches Minecraft for a split second before deleting logisticspipes-0.9.3.132.jar and crashing. See the crash report in "fml-client-latest.log.txt"
   When does this occur? After a clean installation OR after adding Logistics Pipes after state 3 (working without Logistics Pipes)
   Is the installation modified? No.
3. Working without Logistics Pipes
   What is this? The modpack is running fine without Logistics Pipes, a mod that is supposed to be included in the modpack. EDIT: There also seems to be a state in which the mod is not actually deleted, but also not loaded as indicated by the mod rejection when connecting to the server.
   When does this occur? After Logistics Pipes is deleted from a fresh install.
   Is the installation modified? Yes, the mod Logistics Pipes is deleted from the mods folder.

I have tried fixing this issue for 6+ hours now and am out of ideas by now.
Does anyone know how to fix this issue?
Any help is greatly appreciated.

 

[torbeneims]

I have now received a complete instance from a friend and everything works perfectly.

As one would expect, there are many differences between the versions, but the one I find most noteable is the following:

Here you can see the the non-working, freshly downloaded instance on the left is - while having the same version of the Logistics Pipes mod - missing an EnderIO class file within. I had seen something that may link to this issue in the crash report.

Is anyone able to properly fix the issue?