# Managing BIOS Files

This page will help you manage your collection of BIOS files.

## Updating BIOS files

As new versions of MESS come out, the authors sometimes change the system BIOS files in order to make them work properly. As a by-product of this you can sometimes have to update several files.

The simplest way is to use a ROM manager such as clrmamepro with a MESS Bios DATFile as it will identify problems and fix many of them too.

Updated BIOS files can be obtained by dumping them from the original machine or downloading them from the Internet. See the help section "Installing BIOS Files and Software Images" for more details.

##
Verifying BIOS Files

You can let the command line version of MESS audit its own BIOS files using this command...

MESS -verifyroms >missing.txt

This will generate a text file that contains information about all the BIOS files you have problems with and what the problem is.

For MESSGUI it's even easier. On the File menu there is an option called "Audit all systems". If you hit it this window opens...

The list shown is the same as the one generated by the command line version and again shows all of the errors in your ROM files. The only errors that can be resolved in the list are "NOT FOUND" and "CRC ERROR" as the other errors normally mean there is a problem with the only ROM files available to the MESS team.

If a system has stopped working after an update and you can't find anything wrong with the zip file then either there could be a bug in MESS or there has been new development on the game driver. The mess.txt file contains a list of working and non-working systems and is a good start. If this is no good then you can check out the MESS Bugzilla page and see if any news has been posted about it.

Always make sure you scan your BIOS files with a ROM management utility after an update to make sure your set is correct.