Taken from odinms.de/forum

Errors
1) "error code:-2147221000 (DLL for class not found)"
- Explanation: Make sure you copied the Maplestory folder EXACTLY as it
was. Make sure all files are in the Odin folder. Follow the guide here:

http://odinsource.info/index.php?page=connect
If still persisting:
http://odinms.de/forum/showthread.php?t=25646
2) "error code :38 (reached end of file)" (thanks KiliK0101 )
- Explanation: This happens whenever you complete a quest where you
have to get/kill a certain amount of items or monsters. There is no fix
for this. Just re-open OdinMS.
3) "ijl15.dll error"
- Explanation: Follow the guide here: http://odinms.de/forum/showthread.php?t=21203
4) "Application failed to initialize properly {0xc0000005}"
- Explanation: Forestfoxer says: "This is either memory problem or
driver problem. Update your drivers if you did and highest it can go
downgrade and try again." or Make sure the OdinMS.exe is in the copied
Maplestory folder.
5) When I press the login button, nothing happens and the Login button turns grey.
- Explanation: Turkeyidfool says: "That means that you've been put in
line to connect to the server. The server can only hold 1000 people at
a time so just be patient.
-How can they fix it?
Simple, they need money to open new servers. More servers... H-HEY! More people! So donate, donate, donate!"


In-Game Errors
1) "I went to Ms. Tan and now my Item is gone!"
- Explanation: Do a little searching. Ms. Tan is bugged. She takes the items. Do not use her.
2) "I was banned for no reason"
- Explanation: The GM's do not ban without reason. You were banned for
SOMETHING. If you think it is a false ban, please PM a GM. Do not make
a thread. If you were banned and you know why, just give up. Your not
gonna be able to lie to a GM. They have logs.
3) "Cannot connect to server"
- Explanation: Most likely the server is down(to check this go to:http://5.196.25.172)
4) "Is windowed mode(DXWND) allowed?"
- Explanation: Yes it is allowed.
5) "How do I delete a character?"
- Explanation: To do this enter today's date in this format:
year/month/day( 2008/02/18) Remember, this is usually a day ahead.

6) "Incorrect Password"
- Explanation: Either you entered an incorrect password(duh) or you got hacked.
Firstly, make sure you typed in the right password. If you are SURE it
it the right password, then try to change it to something else
Also: Make sure caps lock is off.
7) "Where can I get NX(hair, weapons, etc.)?"
- Explanation: NX can only be obtained through GM events. So, lookout for these events. They are usually held in Kerning.
" I did my job advancement and did not get my HP/MP bonus!"
- Explanation: This is a bug. The GM's do not know the exact formula
for the HP/MP bonus for each class. There is no telling when this will
be fixed.
9) "I cannot drop or trade NX items!"
- Explanation: Make sure you have the latest OdinMs client(http://www.mediafire.com/?xlpo96slewd). If it is an item you just de-equipped, change channel, then try to drop or trade.
10) "When is 3rd job/Ludi/Zipangu/NLC coming out?"
- Explanation: Sorry, but there is no estimated release date for these features XD
10) "After using a chair to sit in I cannot move."
- Explanation: Sorry, but there is no answer for this yet. Don't use the chairs!