error mounting lua/rom.

When i try to click on the computer, it says:

error mounting lua/rom.
Check you have installed computer craft correctly.

What did i do wrong when i installed it, I have forge already installed then i dragged the file into my mods folder? I mea i have other mods but could that really effect it?

Split into new topic.

Has that problem too
So in single player CC work's well,
but on local server we have messege in Comp\Turtle GUI "error mounting lua/rom.
Check you have installed computer craft correctly." at that moment in server console i see

2013-08-17 11:20:39 [INFO] [STDOUT] computercraft: Error running task.
2013-08-17 11:20:39 [INFO] [STDERR] java.lang.NullPointerException
2013-08-17 11:20:39 [INFO] [STDERR] at dan200.computer.core.apis.OSAPI.shutd
own(OSAPI.java:163)
2013-08-17 11:20:39 [INFO] [STDERR] at dan200.computer.core.Computer$2.execu
te(Computer.java:898)
2013-08-17 11:20:39 [INFO] [STDERR] at dan200.computer.core.ComputerThread$1
$1.run(ComputerThread.java:117)
2013-08-17 11:20:39 [INFO] [STDERR] at java.lang.Thread.run(Unknown Source)

minecraft 1.6.2
forge 9.10.0.829(try with 804, 818 with same result)
ComputerCraft 1.56(1.55 the same)

Ask for your help…

I have just installed ComputerCraft and am getting the following message…

Error mounting lua/rom.
Check you have installed ComputerCraft correctly.

I have tried 2 separate installs. One with the folder ComputerCraft1.56 and the other without the 1.56 in the mods folder. They both give the same error. I have no other mods installed other than Forge (latest version).

Did you unzip the mod before putting it into the mods folder?
If yes, just put the zipped version in there.

I also have this problem. When I download the mod, on a Mac, it doesn´t come as a zip-file. I tried now and if you left click the link it downloads as a folder. Don´t know if it unpacks automatically? But if I right-click it comes as a zip-file, and that file has another name than the folder, so it would make sense if the path was wrong.

I will try to use the zip-file to night and see if that solves the problem.