Well, I had that problem once. It saved everytime it said it didnt. Are you sure it didnt save sometimes? I got the problem after opening my map with StarForge.
Btw, its nice having another Dutchman around here.

If you have BroodWar running with that map open, then that's why it won't save. You could also try saving it as a CHK and then opening that with X-Tra.
I have SC open of course, but only at the make game screen, not while using the map, so I think that doesn't matter. Well, the problem occurs at my place only after using StarForge like Da-Darkfire.
I have found a solution for this btw, open the map in SCM toolkit, save it, and there you go. The devil has been driven from the map

I think I've gotten something like this before. If you get that message while trying to save, I think it still saves. I'm not sure but test it if it happens and if you haven't made big changes, and just close the program and see if the changes were saved.
[SOLUTION]Open the map win WinMPQ and delete (listfile)[/SOLUTION]
Whoa!! Sweet, it worked Heimdal. Even though I am not the one that asked the question, but I too had this same problem with mine and my friends old Rpg.

Thanks alot Heimdal!
Dont worry if it says the error message. I was switching between scm draft and sc xtra and made a whole map getting that message. it still saves.
Yeah I know it does, but says the error and you just simply do what Heimdal said and that gets rid of that error message popping up.

i had the same problem
sometimes it is becuz you open with starforge and u had music placed on campaing editor
when you save sometimes it saves other times partially or won't save or will save as corrupted ruinning your map
what heimdal said it's right but you can also restart your comp or reinstall starcraft
have fun
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by the way Da-Darkfire your avatar is cool
What dpes the listfile do?
Only thing I noticed with this when I made a thread about this is that the sound had become an "~unknown" file, and sometimes deleting the listfile recreates it. (I noticed that once)
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OffT:
QUOTE((U)Bolt_Head @ Jul 15 2005, 07:48 PM)
YAY! That was my thread

Files in MPQ archives aren't stored by name. They're stored by a hash (two, actually) of the name. So unless you already know the name of the file, you can't find out what its name is. The (listfile) file simply lists all the files in the archive so that you can see their names. Deleting it will change sounds to ~unknown/... because winMPQ doesn't know the name of the file anymore. This won't have any effect on the way your map is played.