it would be extremely difficult to tell you what was wrong.
I would suggest that you take it apart again, did you have instructions for this or did you just "wing it", and put it back together again.
This time, ensure that everything fits correctly before moving on to the next part.
Some of Apple's laptops use very small clips, molded into the plastic, to hold two parts together. It is very easy to misalign them, still get the screws in, and tight, but end up with a case that is misshapen and with a lid that does not close.
You didn't mention if the Macbook actually worked when you got it back together.
Good Luck
P
OK, so I took a huge risk, and took apart my $2000 Macbook pro to upgrade the wireless card to the Wireless-N from the built in Wireless-G that came with it (yes, you can do that for only $50 bucks if your brave). Well, admittedly, the warranty is expired and I didn't buy Applecare, so I don't really have anything to loose.
I tried to be as careful as possible, but after putting all the screws back on, my computer doesn't look right any more, and it also doesn't latch shut too well either. There is a small gap on both the left and right side of the latch release button!
This seems to be a common problem with these computers after you take them apart. If anyone has any suggestions on how to properly re-assemble it to fix that problem with the gap, I'd appreciate a response.
For what it's worth, I've heard people have this gap problem even when their computer has never been taken apare, so maybe there is no easy fix to this!

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