I have completed all the research for Fusion energy but I am unable to research Fusion energy as "some prerequisite technologies are not researched".

Are u sure to have research all prerequisites? So u have research:

• Advanced electronics 2
• Lithium processing
• Nuclear power
• Utility tech card
• Low density structure
• Kovarex enrichment process

Yes all have been researched.

A mod might have removed one of the prerequisite techs. My game has no kovarex process for example.

Try this command, replace the technology with what you think is missing, see if it unlocks it.

/c game.player.force.technologies["kovarex-enrichment-process"].researched=true

I am missing the Kovarex enrichment process. I am trying to run that command but so far no luck. The game tells me to enter it twice but nothing happens.

If u really have do all step to unlock the tech, u have an obvious incompatibility issue with another mod. One of more mods that u have installed hide vanilla techs, without caring if some other mod use it like a prerequisite and without manage the issue. May if u provide me a list of ur mod I can find a way to fix this problem in the next version.

FNEI 0.3.1 Atomic Artillery 0.1.12 Auto Deconstruct 0.1.17 Bottleneck 0.11.3 Disco Science 1.0.2 ForceFields2 2.3.4 Krastorio2 0.9.16 LSlib 2020.3.16 LoaderRedux 1.5.1 LogisticTrainNetwork 1.13.1 MushroomCloud 1.0.14 Nanobots 3.2.6 Nuclear Fuel 1.1.2 OpteraLib 0.2.1 OutpostPlanner 1.1.4 PlannerCore 0.2.2 base 0.18.22 krastorio2_extended_endgame 0.1.5 stdlib 1.4.2 SpaceMod 0.5.1
The Kovarex Enrichment Process is hidden; it isn't found when searching the "List of Technologies" on the Technology Tree.

Found the gulty, Nuclear Fuel:

Version: 1.1.2
Date: 01. 03. 2020
Bugfixes:
- Migration script now correctly disables Kovarex tech even if not researched

Seems that is not disabled soo correctly ;) .... or u are using a version not updated to the 1.1.2

Whatamaniac,
I suggest u to report this bug on the mod portal of Nuclear Fuel too (of GotLag), may he can fix this quicly than me, also maybe he want know that make other mods not working.

I will think if add an exception script in the next version of K2.

Thank you. I have reported the bug to the mod portal of Nuclear Fuel. I'll let you know what happens.

I was given a script to run in the console and it worked; Kovarex process is back in the game. Thanks!