Launcher won't finish launching due to fatal error.

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statphantom

New Member
Jul 29, 2019
208
0
0
Title:
Launcher won't finish launching due to fatal error.
Launcher Version:
1.4.3
Modpack:
launcher issues, not ModPack.
Modpack Version:
see above
Log Link:
Details of the issue:
the console reads:

From Console: [Fatal Error] :24:10961: XML document structures must start and end within the same entity.
Exception reading modpack file: org.xml.sax.SAXParseException; lineNumber: 24; columnNumber: 10961; XML document structures must start and end within the same entity.

the '3rd party packs' tab just constantly says "Please wait while mods are being loaded..."

after trying to force a mod pack open (infinity in this case), the console reads:

Unhandled exception in Thread[AWT-EventQueue-0,6,main]: java.lang.ArrayIndexOutOfBoundsException: -1
 

seiyumi751

New Member
Jul 29, 2019
1
0
0
I tried doing something myself and it worked for me but no guarantees.
Navigate to C:\Users\<user>\AppData\Local\ftblauncher\ModPacks and you should find some .xml files at the bottom. Open them up in any text editor, probably notepad++ because of the syntax highlighting, and scroll to the bottom.
In one of my .xml files it was missing the closing tag "</modpacks>" as well as a "/>" on the last entry so I just filled them back in and restarted the launcher. Seems to have fixed the issue.

Edit: now that I think about it you could just delete the .xml files and it should regenerate them upon reopening.
Edit 2: I just tried deleting the .xml files and letting it regenerate itself, it seems to not build properly so ignore the first edit.
 
Last edited:

statphantom

New Member
Jul 29, 2019
208
0
0
due to the update it would probably be looking or rebuilding the file differently, so re downloading and installing worked for me, but I did that before trying your method so sorry that I cant validate it.
 

mpmj96

New Member
Jul 29, 2019
1
0
0
I tried doing something myself and it worked for me but no guarantees.
Navigate to C:\Users\<user>\AppData\Local\ftblauncher\ModPacks and you should find some .xml files at the bottom. Open them up in any text editor, probably notepad++ because of the syntax highlighting, and scroll to the bottom.
In one of my .xml files it was missing the closing tag "</modpacks>" as well as a "/>" on the last entry so I just filled them back in and restarted the launcher. Seems to have fixed the issue.

Edit: now that I think about it you could just delete the .xml files and it should regenerate them upon reopening.
Edit 2: I just tried deleting the .xml files and letting it regenerate itself, it seems to not build properly so ignore the first edit.

Dude you are amazing! I had no clue what to actually change in the files but it worked for me. I closed the entities one at a time until I didn't get the error message anymore. I had to close 3 or so lines before it would work fully. Thanks!
 

SoSpartan

New Member
Jul 29, 2019
2
0
0
It looks like some of the download servers have a broken modpack.xml file. Use the fix above, or even simpler, try some of the other download hosts. To change your download host, start the FTB launcher, click the "Options" button on the top row of buttons. Click the "Advanced Options" button on that page, then change the "Download Location" to a different one. In my case, "Los Angeles" worked.

Just be sure to remember that you've changed this option if you have issues in the future. I think the default for this option is: "Automatic" or "CurseCDN".