So i accidentally got rid of some lava rock in my inventory and all the usual sources (BMC, Wheel clan) are exhausted. I looked online and their are a few sources with the invensource.mes on various forums. now the instructions say to copy this into arcanum/data/rules, then sleep for a day when loading the game, however this does not seem to work, the item never shows up in their inventory. Ive also tried using the undat files and manually extracting the data3.mes and then adding the entry into the various vendors so im able to purchase it at stores. This does not work either, nothing shows up in their inventory there either. so, basically what im asking is, how can i fix this, or does anyone know of an alternative source of lava rock?

Dunno if you got this fixed, I cant help but I will give it a lil' bump so it shows that this forum has had some recent activity, it may grab someones attention that can help.

If you're on Windows 7, you may have to try both
C:\Program Files (x86)\GOG.com\Arcanum\data
and
C:\Users\<YOUR USERNAME>\AppData\Local\VirtualStore\Program Files (x86)\GOG.com\Arcanum\data

Where are you resting? You probably need to be in a different town. I know that you need to at least be a screen away to make a merchant refresh (if the shop is on-screen when you rest, it doesn't refresh at all) - and if you want it to reset from a file, I suspect you may need to be in a different town, so go somewhere that isn't a source, save there, replace the file, load up, rest, then travel back to the target store. Irritating process, but your current map is probably saved in some local state file, so you need to be elsewhere to read from main files.

Finally, as far as invensource.mes goes, you may need to *add* an item to it it get it to show up, as the save games may just flag what things have been taken.

The "rules" folder probably does not exist yet, you'll need to create it.
Creating in in
b:/games/arcanum/data
should work.

If you did not install to either "Program Files" directory, then you (probably) shouldn't have an entry in VirtualStore, which aren't links - it's part of the special transparent protection that Windows 7 applies to protected folders, which I presume "b:/games/" is not.