Problems Removing a Mod, Missing items/block and Java.io.IOException Error

Having some trouble with Forge after removing a mod, I go to load my world(s) after removing it, and I get a prompt telling me that certain block/items are missing and that if I continue said blocks/items will get removed and that a world backup will be created in my saves directory.

I say yes, since no takes me back to the title screen with nothing changed, and I get a second prompt saying: "The world backup could not be created. Java.io.IOException: The filename, directory name, or volume label syntax is incorrect." and get redirected back to the title screen.

When I removed the mod from my mods folder in my .minecraft folder I went into the config folder and deleted the config files for both the mod and mod dependency needed to use it out of habit, so as to avoid clutter. I know I can fix this by restoring the mod, but what can I do to remove it altogether? Is the deletion of the config files the reason for these errors?

Any help would be appreciated, I read the Common Problems section of the Read Before Posting thread, but found nothing matching my problem, even if it feels fairly common in my honest opinion, any feedback would be appreciated, new to the fourms so if I missed anything to post, please let me know, the mod I am trying to remove/did remove and is now causing errors is the Balanced Exchange Mod, also I use the latest 1.7.2 release of Forge.

EDIT: I restored both the mod files and the config files, started Minecraft and loaded my world without problem, and then exited and only deleted the mod files and restarted and reloaded my world, everything seems to be fine now, no error pop ups, seems I've guessed the problem, too much of a neat freak haha...

What's your operating system? Is the .minecraft directory in a normal directory or some file share? Which file system?

Edit: Your world name probably contained special characters, which should be fixed in the next Forge version.