What does "Archive does not contain 'android-something.txt'" mean? So I am trying to flash my OnePlus One with CM12s through fastboot on command prompt, but whenever I type fastboot update romname.zip I am presented with:

archive does not contain 'android-info.txt'
archive does not contain 'android-product.txt'
error: update package has no android-info.txt or android-product.txt


the specific build I am using can be found here It is the build ending in 8, or the one submitted on 2015-07-08

What have I done wrong?
I never flashed a ROM using a .zip in fastboot. The proper way I've ever seen is to flash individual files, and some of the important commands are:

fastboot flash boot boot.img
fastboot flash cache cache.img
fastboot flash recovery recovery.img
fastboot flash system system.img
fastboot flash userdata userdata.img // 64GB users need userdata_64G.img


Provided that you do have these individual files in your .zip.

These kind of zips are called as "fastboot zips" or "fastboot images", while those requiring a custom Recovery (as keepclam mentioned) are plainly known as normal recovery-flashable zips.

I'm not aware of custom ROMs providing "fastboot zips", but if you intend to gain an experience of flashing such zips, I would suggest flashing a stock CM12s. You can find the related info on OnePlus Forums here.

About the error, it says you don't have android-info.txt. That's true that you probably don't have it because as I said custom ROMs usually don't provide "fastboot zips" which has this file. And I also said to try stock CM12s fastboot zip since it has that android-info.txt whose content would be like:

require version-trustzone=TZ.BF.2.0-2.0.0109


I think things would be clear for now.