File corruption and when to suspect it

[Zaflis]

Commonly seen sentence is,

"I see mod loaded ingame and things 1,2,3 and 4 works but feature 5 does not. I guess i'll download and reinstall the mod again."

 

Do this test:

1) Choose any .7z mod file of your choice, i'll go with for example "RaceMenu v3...7z". Copy it and rename the copy to "_test.7z".

 

2) Right click the "_test.7z" file and "open with notepad++" (or regular notepad).

 

3) Pick any character you see and replace it with some other character. For example some "d", replace with "n" then save and close. Now this file is officially corrupted.

 

4) Now open it in 7-Zip and try to extract. It should throw a bunch of errors and in my case the 2 .esp files of Racemenu had 0 bytes in them.

 

So what we learned, if compressed files are corrupted you don't actually get any info out of them at all. Compressing something doesn't mean that file is necessarily even structured in linear order anymore. 1 byte that is changed can have references to several different files, and extractor apps will definitely see that from the file integrity checks - CRC.

 

However i do understand that decompression algorithms are smart and also have built-in corruption fixes for some bit-errors. This doesn't mean that they will always work though.

If a mod file is corrupted, you won't see any of its content in game and it could or should crash the game on load.

 

The 99.99% more likely thing to suspect is some other mistake you did during the installation of the mod, or in required mods of the mod. Even thinking about needing to redownload something is almost never necessary.

 

Edit: Oh and what happens when i try to install a corrupted file with MO2, the install progress for me just stucks at 0%, then gives error popup after. So it doesn't install anything.