HL ErrorCodes

Hotline Protocol

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Error Codes

Error codes in the Hotline protocol are 4-byte (32-bit) integers. A value of 0 always indicates "No Error" (Success).

General Errors

These are commonly returned in the Transaction Header during basic operations.

Code (Dec)	Constant	Description
0	err_None	Success / No Error.
-1	err_Generic	A non-specific error occurred.
1	err_NotConnected	The operation requires a connection that is no longer active.
2	err_Socket	A low-level TCP/IP socket error occurred.

Login & Access Errors

These typically occur during Transaction 107 (Login) or when trying to perform restricted actions.

Code (Dec)	Constant	Description
1000	err_LoginFailed	Invalid username or password.
1001	err_AlreadyLoggedIn	The user is already connected to the server.
1002	err_AccessDenied	The user does not have the required Access Bit for this action.
1003	err_UserBanned	The user's IP or account has been banned from the server.
1004	err_ServerFull	The server has reached its maximum user limit.

File & Transfer Errors

Returned during file system transactions (200-213).

Code (Dec)	Constant	Description
2000	err_FileNotFound	The requested file or folder path does not exist.
2001	err_FileInUse	The file is currently being accessed by another process.
2002	err_DiskFull	The server disk is full; upload cannot complete.
2003	err_TransferFailed	The binary transfer was interrupted or failed checksum.

News & Messaging Errors

Code (Dec)	Constant	Description
3000	err_NewsFull	The news database cannot accept more posts.
3001	err_MsgRefused	The recipient has the "Refuse Private Messages" flag set.

Field ID 100 (Error Text)

Sometimes, a server will return a generic error code in the header but include Field 104 (Error Text) in the parameter list. This field contains a human-readable string explaining the error in more detail (e.g., "Maintenance in progress, please try again in 10 minutes").