Error Codes & Their Meanings

⚙️ HTTP Status Codes

Informational (100–199)

100 — Continue
101 — Switching Protocols
102 — Processing
103 — Early Hints
104 — Upload Resumption Supported
105-199 — Unassigned

Success (200–299)

200 — OK
201 — Created
202 — Accepted
203 — Non-Authoritative Information
204 — No Content
205 — Reset Content
206 — Partial Content
207 — Multi-Status
208 — Already Reported
209-225 — Unassigned
226 — IM Used
227-299 — Unassigned

Redirection (300–399)

300 — Multiple Choices
301 — Moved Permanently
302 — Found
303 — See Other
304 — Not Modified
305 — Use Proxy
306 — Unused
307 — Temporary Redirect
308 — Permanent Redirect
309-399 — Unassigned

Client Errors (400–499)

400 — Bad Request
401 — Unauthorized
402 — Payment Required
403 — Forbidden
404 — Not Found
405 — Method Not Allowed
406 — Not Acceptable
407 — Proxy Authentication Required
408 — Request Timeout
409 — Conflict
410 — Gone
411 — Length Required
412 — Precondition Failed
413 — Payload Too Large
414 — URI Too Long
415 — Unsupported Media Type
416 — Range Not Satisfiable
417 — Expectation Failed
418 — I'm a teapot ☕
419 — Unassigned
420 — Unassigned
421 — Misdirected Request
422 — Unprocessable Content
423 — Locked
424 — Failed Dependency
425 — Too Early
426 — Upgrade Required
427 — Unassigned
428 — Precondition Required
429 — Too Many Requests
430 — Unassigned
431 — Request Header Fields Too Large
432-450 — Unassigned
451 — Unavailable For Legal Reasons
452-499 — Continue

Server Errors (500–599)

500 — Internal Server Error
501 — Not Implemented
502 — Bad Gateway
503 — Service Unavailable
504 — Gateway Timeout
505 — HTTP Version Not Supported
506 — Variant Also Negotiates
507 — Insufficient Storage
508 — Loop Detected
509 — Bandwidth Limit Exceeded
510 — Not Extended (OBSOLETED)
511 — Network Authentication Required
512-599 — Unassigned

🔌 Network Errors

ERR_CONNECTION_REFUSED — Server rejected connection
ERR_CONNECTION_RESET — Connection forcibly closed
ERR_CONNECTION_ABORTED — Connection aborted unexpectedly
ERR_CONNECTION_CLOSED — Connection closed before response was received
ERR_CONNECTION_ALTERNATE_PROTOCOL — Alternate protocol suggested but failed
ERR_NAME_NOT_RESOLVED — DNS lookup failed
ERR_INTERNET_DISCONNECTED — No active internet connection
ERR_NETWORK_CHANGED — Network configuration changed
ERR_NETWORK_IO_SUSPENDED — Network I/O temporarily suspended, often due to system constraints
ERR_NETWORK_ACCESS_DENIED — Network access blocked by system policy of firewall
ERR_TIMED_OUT — Server took too long to respond
ERR_SSL_PROTOCOL_ERROR — SSL handshake failed
ERR_SSL_VERSION_OR_CIPHER_MISMATCH — Incompatible SSL version or cipher
ERR_SSL_CLIENT_AUTH_CERT_NEEDED — Server requests client certificate for authentication
ERR_SSL_RENEGOTIATION_REQUESTED — Server requested SSL renegotiation
ERR_CERT_COMMON_NAME_INVALID — Certificate name mismatch
ERR_CERT_AUTHORITY_INVALID — Untrusted certificate authority
ERR_CERT_DATE_INVALID — Certificate expired or not yet valid
ERR_CERT_WEAK_SIGNATURE_ALGORITHM — Certificate uses deprecated signature algorithm
ERR_CERT_PINNED_KEY_NOT_IN_CERT_CHAIN — Pinned key missing from certificate chain
ERR_ADDRESS_UNREACHABLE — IP address unreachable from client
ERR_TUNNEL_CONNECTION_FAILED — Proxy tunnel failed
ERR_EMPTY_RESPONSE — Server sent no data
ERR_RESPONSE_HEADERS_TOO_BIG — Server headers exceeded limit
ERR_RESPONSE_HEADERS_MULTIPLE_CONTENT_DISPOSITION — Conflicting content disposition headers
ERR_RESPONSE_HEADERS_MULTIPLE_CONTENT_LENGTH — Multiple content-length headers detected
ERR_CONTENT_DECODING_FAILED — Compression decoding failed
ERR_CONTENT_LENGTH_MISMATCHED — Declared content length doesn't match actual payload
ERR_TOO_MANY_REDIRECTS — Infinite redirect loop detected
ERR_PROXY_CONNECTION_FAILED — Failed to connect to proxy server
ERR_CACHE_MISS — Request requires revalidation from the server
ERR_BLOCKED_BY_CLIENT — Request blocked by client-side extension or filter
ERR_BLOCKED_BY_RESPONSE — Request blocked by server (e.g., CORS or security headers)
ERR_FAILED — Generic failure with no specific classification
ERR_UNSAFE_PORT — Attempted connection to a restricted port
ERR_FILE_NOT_FOUND — Requested local file not found (common in file:// URLs)
ERR_INVALID_RESPONSE — Server response was malformed or unexpected
ERR_INVALID_CHUNKED_ENCODING — Malformed chunked transfer encoding
ERR_SOCKET_NOT_CONNECTED — Attempted operation on a socket that isn't connected
ERR_SOCKET_CLOSED — Socket closed unexpectedly during transmission
ERR_QUIC_PROTOCOL_ERROR — QUIC transport layer failure (used by modern browsers)
ERR_HTTP2_PROTOCOL_ERROR — HTTP/2 stream or framing error

🖥 Windows System Errors

Error Code Ranges:

500-15999 — Extended system errors
16000-16999 — Installer errors
17000-17999 — RPC errors
18000-18999 — Cluster errors
19000+ — Custom HRESULT and NTSTATUS codes

Error Codes:

I will be adding more of these throughout the week since there are a lot of them.
000 (0x0) — ERROR_SUCCESS
001 (0x1) — ERROR_INVALID_FUNCTION
002 (0x2) — ERROR_FILE_NOT_FOUND
003 (0x3) — ERROR_PATH_NOT_FOUND
004 (0x4) — ERROR_TOO_MANY_OPEN_FILES
005 (0x5) — ERROR_ACCESS_DENIED
006 (0x6) — ERROR_INVALID
007 (0x7) — ERROR_ARENA_TRASHED
008 (0x8) — ERROR_NOT_ENOUGH_MEMORY
009 (0x9) — ERROR_INVALID_BLOCK
010 (0xA) — ERROR_BAD_ENVIRONMENT
011 (0xB) — ERROR_BAD_FORMAT
012 (0xC) — ERROR_INVALID_ACCESS
013 (0xD) — ERROR_INVALID_DATA
014 (0xE) — ERROR_OUTOFMEMORY
015 (0xF) — ERROR_INVALID_DRIVE
016 (0x10) — ERROR_CURRENT_DIRECTORY
017 (0x11) — ERROR_NOT_SAME_DEVICE
018 (0x12) — ERROR_NO_MORE_FILES
019 (0x13) — ERROR_WRITE_PROTECT
020 (0x14) — ERROR_BAD_UNIT
021 (0x15) — ERROR_NOT_READY
022 (0x16) — ERROR_BAD_COMMAND
023 (0x17) — ERROR_CRC
024 (0x18) — ERROR_BAD_LENGTH
025 (0x19) — ERROR_SEEK
026 (0x1A) — ERROR_NOT_DOS_DISK
027 (0x1B) — ERROR_SECTOR_NOT_FOUND
028 (0x1C) — ERROR_OUT_OF_PAPER
029 (0x1D) — ERROR_WRITE_FAULT
030 (0x1E) — ERROR_READ_FAULT
031 (0x1F) — ERROR_GEN_FAILURE
032 (0x20) — ERROR_SHARING_VIOLATION
033 (0x21) — ERROR_LOCK_VIOLATION
034 (0x22) — ERROR_WRONG_DISK
035 (0x24) —
036 (0x24) — ERROR_SHARING_BUFFER_EXCEEDED
037 (0x25) —
038 (0x26) — ERROR_HANDLE_EOF
039 (0x27) — ERROR_HANDLE_DISK_FULL
040 (0x28) —
041 (0x29) —
042 (0x2A) —
043 (0x2B) —
044 (0x2C) —
045 (0x2D) —
046 (0x2E) —
047 (0x2F) —
048 (0x30) —
049 (0x31) —
050 (0x32) — ERROR_NOT_SUPPORTED
051 (0x33) — ERROR_REM_NOT_LIST
052 (0x34) — ERROR_DUP_NAME
053 (0x35) — ERROR_BAD_NETPATH
054 (0x36) — ERROR_NETWORK_BUSY
055 (0x37) — ERROR_DEV_NOT_EXIST
056 (0x38) — ERROR_TOO_MANY_CMDS
057 (0x39) — ERROR_ADAP_HDW_ERR
058 (0x3A) — ERROR_BAD_NET_RESP
059 (0x3B) — ERROR_UNEXP_NET_ERR
060 (0x3C) — ERROR_BAD_REM_ADAP
061 (0x3D) — ERROR_PRINTQ_FULL
062 (0x3E) — ERROR_NO_SPOOL_SPACE
063 (0x3F) — ERROR_PRINT_CANCELLED
064 (0x40) — ERROR_NETNAME_DELETED
065 (0x41) — ERROR_NETWORK_ACCESS_DENIED
066 (0x42) — ERROR_BAD_DEV_TYPE
067 (0x43) — ERROR_BAD_NET_NAME
068 (0x44) — ERROR_TOO_MANY_NAMES
069 (0x45) — ERROR_TOO_MANY_SESS
070 (0x46) — ERROR_SHARING_PAUSED
071 (0x47) — ERROR_REQ_NOT_ACCEP
072 (0x48) — ERROR_REDIR_PAUSED
073 (0x49) —
074 (0x4A) —
075 (0x4B) —
076 (0x4C) —
077 (0x4D) —
078 (0x4E) —
079 (0x4F) —
080 (0x50) — ERROR_FILE_EXISTS
081 (0x51) —
082 (0x52) — ERROR_CANNOT_MAKE
083 (0x53) — ERROR_FAIL_I24
084 (0x54) — ERROR_OUT_OF_STRUCTURES
085 (0x55) — ERROR_ALREADY_ASSIGNED
086 (0x56) — ERROR_INVALID_PASSWORD
087 (0x57) — ERROR_INVALID_PARAMETER
088 (0x58) — ERROR_NET_WRITE_FAULT
089 (0x59) — ERROR_NO_PROC_SLOTS
090 (0x5A) —
091 (0x5B) —
092 (0x5C) —
093 (0x5D) —
094 (0x5E) —
095 (0x5F) —
096 (0x60) —
097 (0x61) —
098 (0x62) —
099 (0x63) —
100 (0x64) — ERROR_TOO_MANY_SEMAPHORES
101 (0x65) — ERROR_EXCL_SEM_ALREADY_OWNED
102 (0x66) — ERROR_SEM_IS_SET
103 (0x67) — ERROR_TOO_MANY_SEM_REQUESTS
104 (0x68) — ERROR_INVALID_AT_INTERRUPT_TIME
105 (0x69) — ERROR_SEM_OWNER_DIED
106 (0x6A) — ERROR_SEM_USER_LIMIT
107 (0x6B) — ERROR_DISK_CHANGE
108 (0x6C) — ERROR_DRIVE_LOCKED
109 (0x6D) — ERROR_BROKEN_PIPE
110 (0x6E) — ERROR_OPEN_FAILED
111 (0x6F) — ERROR_BUFFER_OVERFLOW
112 (0x70) — ERROR_DISK_FULL
113 (0x71) — ERROR_NO_MORE_SEARCH_HANDLES
114 (0x72) — ERROR_INVALID_TARGET_HANDLE
115 (0x73) —
116 (0x74) —
117 (0x75) — ERROR_INVALID_CATEGORY
118 (0x76) — ERROR_INVALID_VERIFY_SWITCH
119 (0x77) — ERROR_BAD_DRIVER_LEVEL
120 (0x78) — ERROR_CALL_NOT_IMPLEMENTED
121 (0x79) — ERROR_SEM_TIMEOUT
122 (0x7A) — ERROR_INSUFFICIENT_BUFFER
123 (0x7B) — ERROR_INVALID_NAME
124 (0x7C) — ERROR_INVALID_LEVEL
125 (0x7D) — ERROR_NO_VOLUME_LABEL
126 (0x7E) — ERROR_MOD_NOT_FOUND
127 (0x7F) — ERROR_PROC_NOT_FOUND
128 (0x80) — ERROR_WAIT_NO_CHILDREN
129 (0x81) — ERROR_CHILD_NOT_COMPLETE
130 (0x82) — ERROR_DIRECT_ACCESS_HANDLE
131 (0x83) — ERROR_NEGATIVE_SEEK
132 (0x84) — ERROR_SEEK_ON_DEVICE
133 (0x85) — ERROR_IS_JOIN_TARGET
134 (0x86) — ERROR_IS_JOINED
135 (0x87) — ERROR_IS_SUBSTED
136 (0x88) — ERROR_NOT_JOINED
137 (0x89) — ERROR_NOT_SUBSTED
138 (0x8A) — ERROR_JOIN_TO_JOIN
139 (0x8B) — ERROR_SUBST_TO_SUBST
140 (0x8C) — ERROR_JOIN_TO_SUBST
141 (0x8D) — ERROR_SUBST_TO_JOIN
142 (0x8E) — ERROR_BUSY_DRIVE
143 (0x8F) — ERROR_SAME_DRIVE
144 (0x90) — ERROR_DIR_NOT_ROOT
145 (0x91) — ERROR_DIR_NOT_EMPTY
146 (0x92) — ERROR_IS_SUBST_PATH
147 (0x93) — ERROR_IS_JOIN_PATH
148 (0x94) — ERROR_PATH_BUSY
149 (0x95) — ERROR_IS_SUBST_TARGET
150 (0x96) — ERROR_SYSTEM_TRACE
151 (0x97) — ERROR_INVALID_EVENT_COUNT
152 (0x98) — ERROR_TOO_MANY_MUXWAITERS
153 (0x99) — ERROR_INVALID_LIST_FORMAT
154 (0x9A) — ERROR_LABEL_TOO_LONG
155 (0x9B) — ERROR_TOO_MANY_TCBS
156 (0x9C) — ERROR_SIGNAL_REFUSED
157 (0x9D) — ERROR_DISCARDED
158 (0x9E) — ERROR_NOT_LOCKED
159 (0x9F) — ERROR_BAD_THREADID_ADDR
160 (0xA0) — ERROR_BAD_ARGUMENTS
161 (0xA1) — ERROR_BAD_PATHNAME
162 (0xA2) — ERROR_SIGNAL_PENDING
163 (0xA3) —
164 (0xA4) — ERROR_MAX_THRDS_REACHED
165 (0xA5) —
166 (0xA6) —
167 (0xA7) — ERROR_LOCK_FAILED
168 (0xA8) —
169 (0xA9) —
170 (0xAA) — ERROR_BUSY
171 (0xAB) — ERROR_DEVICE_SUPPORT_IN_PROGRESS
172 (0xAC) —
173 (0xAD) — ERROR_CANCEL_VIOLATION
174 (0xAE) — ERROR_ATOMIC_LOCKS_NOT_SUPPORTED
175 (0xAF) —
176 (0xB0) —
177 (0xB1) —
178 (0xB2) —
179 (0xB3) —
180 (0xB4) — ERROR_INVALID_SEGMENT_NUMBER
181 (0xB5) —
182 (0xB6) — ERROR_INVALID_ORDINAL
183 (0xB7) — ERROR_ALREADY_EXISTS
184 (0xB8) —
185 (0xB9) —
186 (0xBA) — ERROR_INVALID_FLAG_NUMBER
187 (0xBB) — ERROR_SEM_NOT_FOUND
188 (0xBC) — ERROR_INVALID_STARTING_CODESEG
189 (0xBD) — ERROR_INVALID_STACKSEG
190 (0xBE) — ERROR_INVALID_MODULETYPE
191 (0xBF) — ERROR_INVALID_EXE_SIGNATURE
192 (0xC0) — ERROR_EXE_MARKED_INVALID
193 (0xC1) — ERROR_BAD_EXE_FORMAT
194 (0xC2) — ERROR_ITERATED_DATA_EXCEEDS_64k
195 (0xC3) — ERROR_INVALID_MINALLOCSIZE
196 (0xC4) — ERROR_DYNLINK_FROM_INVALID_RING
197 (0xC5) — ERROR_IOPL_NOT_ENABLED
198 (0xC6) — ERROR_INVALID_SEGDPL
199 (0xC7) — ERROR_AUTODATASEG_EXCEEDS_64k
200 (0xC8) — ERROR_RING2SEG_MUST_BE_MOVABLE
267 (0x10B) — ERROR_DIRECTORY
400 (0x190) — ERROR_THREAD_MODE_ALREADY_BACKGROUND
401 (0x191) — ERROR_THREAD_MODE_NOT_BACKGROUND
402 (0x192) — ERROR_PROCESS_MODE_ALREADY_BACKGROUND
403 (0x193) — ERROR_PROCESS_MODE_NOT_BACKGROUND
487 (0x1E7) — ERROR_INVALID_ADDRESS
995 — ERROR_OPERATION_ABORTED
0x0000007B — Innaccessible Boot Device
0x80004005 — Unspecified Error
0x80070005 — Access Denied
0x8007000E — Not Enough Memory
0x80070570 — File or Directory is Corrupted
0x80070643 — Fatal error during installation
0x80072EE7 — Server Name or Address Could Not Be Resolved
0x80240017 — Windows Update Failed
0x803f8001 — Xbox/Microsoft Store App Launch Failure
0xC0000005 — Access Violation

🍏 Mac Errors

-36 — I/O Error (Finder can't read/write)
-43 — File Not Found
-50 — Invalid Parameter
-8003 — Trash Empty Failure
I am working on finding more of these to add to the list.

Return home