PackagingResults:Error: Error Unknown Cook Failure

anonymous_user_34605e88 · December 22, 2015, 11:36am

When i package for windows 64 bit it going through and at the end it says in message log
PackagingResults:Error: Error Unknown Cook Failure
My build config in on Shipping i package for windows 64 bit

Sean_L · December 23, 2015, 1:02pm

Could you provide the full outpug log? I’d like to take a look at it to see if there are any other errors.

anonymous_user_7a011e34 · March 24, 2016, 9:40pm

Thanks for your awnser! This did work for me once I deleted a file it was complaining about! Thanks again!

anonymous_user_6872a4e9 · June 23, 2016, 2:29am

Hi Sean. I try your method but still can’t package project. Could you help me to take a look my output log?

Sean_L · June 23, 2016, 12:15pm

Hey Edmond Lo,

Please create a new post in the Packaging & Deployment section and ensure to attach your output log after the packaging fails. Once you have created the new post, post the link to it here and we can investigate the issue separately.

Thanks!

Rama · July 21, 2016, 4:01am

#Solution

I want Sean to get the credit for this answer, but I wanted to share that for me this solution did not work, I had a real legitimate BP compile error, but this was reported as Unknown packaging error…

Deep in the packaging log there was this line that tipped me off:

MainFrameActions: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.07.21-03.48.09:672][  0]LogInit:Display: Warning/Error Summary (Unique only)
MainFrameActions: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.07.21-03.48.09:672][  0]LogInit:Display: -----------------------------------
MainFrameActions: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.07.21-03.48.09:672][  0]LogInit:Display: LogBlueprint:Error: [compiler JoyBallBP_Original] Error Missing Event 'BP_PlayJoyAccelerationByOtherPlayerParticles' for  Event BP_PlayJoyAccelerationByOtherPlayerParticles

For a BP I was not even using

I opened it, and hit recompile, and the red sign went away and I packaged successfully after that.

I was doing tests and removed 4.5gb of content and thought that was the reason, but really it was just 1 BP and its 1 compile error.

My only suggestion would be that if the packaging system reports a LogBlueprint:Error, it should probably say

“Could not compile due to Blueprint Compile Errors”

and that would be a lot more clear than “unknown packaging error”

Sean could you consider making that a feature request?

What I am highlighting is that if the packaging system knows there are BP compile errors, it should say so, instead of leading us all on wild goose chases for things other than simple obvious BP compile issues.

#Summary

Reviewing the whole log helped me find it, but if the last line of packaging could simply tell me I have a BP compile error that would really expedite my debugging work flow

Thank you for UE4!

#

Rama

Sean_L · July 21, 2016, 12:35pm

Hey Rama,

Thank you for providing your solution. I have taken your suggestion for additional detail in error messages during packaging failures, and have entered a feature request, UE-33618.

Have a great day!

grimsmote · August 27, 2016, 7:18am

I had a similar error after setting up streaming levels, cleaned all my blueprints up to no avail - I went through the streaming levels and reset the game mode for those levels, which fixed the error. I guess they must have been calling a first person character blueprint that was creating the issue. Just adding this comment to help others who experience the issue in future!

anonymous_user_166d5dd8 · August 27, 2016, 8:44am

This helped me, go into Blueprints up at the top near settings, click open blueprint level and delete anything that says ERROR and anything connected to it, save and try packaging again

Allenheathx · October 15, 2016, 5:26pm

Clarity with packaging errors would be really nice. So far the most difficult aspect of development (including multiplayer networking) has surprisingly been packaging. I’ve spent weeks on trouble shooting packaging problems. Usually I end up migrating the whole game to a new file and it works after that but as the game gets deeper into development, servers get set up, online subsystem etc…the migration process itself can easily take 3-5 days between work and compiling times (all work I’ve already done at least 3 times which makes it more frustrating). In most cases it is probably some unused bp in the depths of the game that is referencing some variable that isn’t there but without any direction the tiny little problem becomes a show stopper when it comes to packaging. Either clarity with the problem of cook errors or more leniency in terms of package success’s would be nice. Sorry done with my rant, Love Unreal whatever the case but packaging really is surprisingly larger hassle then expected.

Allenheathx · October 15, 2016, 5:31pm

A cool feature would be if you could do something like “tag” all used assets and unreal automatically “prioritized” all tagged files and all files included in “tagged” files (so all textures in the material, all materials in the particle and all bp that used the particle would be “prioritized” regardless of their location). And then all untagged files were put in a sort of lower priority bracket that bypassed cook errors or packaging altogether. Anyway just a naive idea that could help.

Linderdavid.com · March 27, 2017, 4:35pm

In the Output Log it should say something like cook failure at line ##.
Right click on your unreal project file>open in notepad>go to the line that ## is referencing. There you will find what the problem is or at least what you have to fix.

For me it was a plugin that I didn’t use and didn’t have loaded on that machine so it was as easy as deleting a few lines of code, for you it might be that a BP has an issue.

Sam54123 · November 4, 2017, 7:05pm

Are you kidding me!! I did that and when I relaunched the engine, it deleted my entire content folder!!

SSkipper · December 3, 2017, 3:05pm

I followed this forum post to the T, and I finally found the error that was preventing my game from cooking. Hurraayyy!!! Then I lost control over my player character. I did exactly what is written here. I went into my " project folder and deleted the Saved, Intermediate, and Config folders, and restarted my computer." I then tested to see if I could cook and I could not. I found the error that was messing with the cook, just some messily texture file. I deleted it and then the game cooked. Now I can’t move my character and the game is set to game mode base. Tried to change it back to third person but I can’t. The error message pops up and is gone before I can read it.
For anyone reading this. If you really want to cook your game so that you can package… and there is some “unknown error”… don’t be dumb, just go into your “Event Log” type in “Error” at the top of the search bar and read each line until you can figure out what went wrong. Do not follow the advice on this thread.

anonymous_user_28fe00231 · August 22, 2018, 4:58pm

SSkipper is right, I did have this problem also yesterday it took me more then 6 hours until i realized to look carefully in the output logs, and the errors where kinda clearly written there and you just had to fix them.

anonymous_user_796dcc8f · April 30, 2019, 2:02pm

“go into your project folder and delete the Saved, Intermediate, and Config folders, and restart your computer. After doing all of this, give it another try and let me know if that helps”
I just lost hours of work because of this.

anonymous_user_12493071 · May 8, 2019, 1:31pm

Just lost hours upon hours of works since I assumed the staff knew what they were talking about when they said “…delete the Saved, Intermediate, and Config folders…” Please delete your post Sean L as I see others have also already fallen victim to this and more by the day.

RogueSheep · October 5, 2019, 9:13am

Why in earth’s name would you want to delete your config folder??
This will cause you to lose a lot of necessary configuration from your project settings, like your ‘Maps & Modes’ and input.

Please explain or revise your answer Sean before (more) people start losing work following this suggestion.

RowelCaps · October 4, 2020, 4:04pm

Thank you Sean Flint, for teaching me a valuable lesson to not delete the config folder ever again. I’ve learned it the hard way. Excuse me while I change the variables of hundreds of blueprints. This is so fun!

Up next, I will try to delete the source and content folder. I wonder what valuable lesson that I might learn. I hope deleting that will fix my packaging problems.

but hey if that did not work, Might as well delete system32 too!

timmykiller123 · March 25, 2021, 9:31am

In your Output Log scroll to the approximate location of where it shows the unknown error. On one of the lines, it should say something like “Go to C:\Users\My User\AppData\Roaming\Unreal Engine\AutomationTool\Logs\C+Program+Files+Epic+Games+UE_4.26\Log.txt for more details”. Open the file in notepad and see where the error is specified. For me, it said that access was denied, so I went into my desktop, right-clicked on Unreal Engine and selected “Run as Administrator”. This fixed the problem and allowed me to package my project.

PS. You can check which apps are running as administrator in the Windows Task Manager