Commonly encountered error codes and messages. Some categories (such as HTTP) have standardized codes, while others (hardware, mathematics, and human errors) often use vendor- or application-specific codes rather than universal standards.

Hardware Errors

BIOS / POST Errors

• POST Error 161
• POST Error 162
• POST Error 163
• POST Error 164
• POST Error 201
• POST Error 301
• POST Error 601
• POST Error 1780
• POST Error 1782
• CMOS Checksum Error
• CMOS Battery Failure
• CPU Fan Error
• Keyboard Error
• No Boot Device Found
• Hard Disk Failure
• Memory Test Failed
• Processor Thermal Trip
• SMART Status BAD
• PCI Device Error

Hard Drive / SSD Errors

• SMART Error
• Disk Read Error
• I/O Device Error
• CRC Error
• Drive Not Ready
• Device Timeout
• Read Failure
• Write Failure
• Bad Sector Error
• File System Corruption

RAM Errors

• Memory Parity Error
• ECC Memory Error
• Memory Allocation Failure
• RAM Initialization Failed
• DIMM Failure

Printer Errors

• Error 49
• Error 50
• Error 79
• Error B200
• Paper Jam
• Out of Paper
• Toner Low
• Cartridge Error
• Offline Printer
• Communication Error

GPU Errors

• Video TDR Failure
• GPU Timeout
• Graphics Device Lost
• Display Driver Stopped Responding
• DirectX Device Removed

USB Errors

• USB Device Not Recognized
• USB Descriptor Failed
• Code 10
• Code 43
• Code 28

Windows Device Manager Errors

• Code 1
• Code 3
• Code 10
• Code 12
• Code 18
• Code 19
• Code 21
• Code 22
• Code 24
• Code 28
• Code 31
• Code 32
• Code 37
• Code 39
• Code 43
• Code 45
• Code 47
• Code 52

Human Errors

Human errors are usually represented by messages rather than standardized numeric codes.

Authentication

• Invalid Username
• Invalid Password
• Incorrect OTP
• Account Locked
• Session Expired
• Unauthorized Access
• Access Denied

Input Errors

• Invalid Email
• Invalid Phone Number
• Invalid Date
• Invalid PIN
• Invalid File
• Invalid CAPTCHA
• Invalid Input
• Required Field Missing
• Duplicate Entry
• Invalid Format

User Action Errors

• Permission Denied
• File Already Exists
• File Not Found
• Unsupported Operation
• Upload Failed
• Download Failed
• Payment Cancelled
• Checkout Failed
• Submission Failed

Application Errors

• Validation Failed
• Request Rejected
• Operation Cancelled
• Action Not Allowed
• Confirmation Required
• Resource Already Exists

Mathematics Errors

Arithmetic Errors

• Divide by Zero
• Overflow Error
• Underflow Error
• Floating Point Exception
• Numeric Overflow
• Numeric Underflow

Calculation Errors

• Invalid Operand
• Invalid Expression
• Arithmetic Exception
• Domain Error
• Range Error
• Precision Loss
• Rounding Error

Programming Math Errors

Java

• ArithmeticException
• NumberFormatException

Python

• ZeroDivisionError
• OverflowError
• FloatingPointError
• ValueError

JavaScript

• RangeError
• NaN
• Infinity

C/C++

• SIGFPE
• Floating Point Exception

Spreadsheet Errors

Excel

• #DIV/0!
• #VALUE!
• #NAME?
• #NUM!
• #N/A
• #NULL!
• #REF!
• #SPILL!
• #CALC!

Networking Errors

HTTP Status Codes

1xx

• 100 Continue
• 101 Switching Protocols
• 102 Processing
• 103 Early Hints

2xx

• 200 OK
• 201 Created
• 202 Accepted
• 203 Non-Authoritative Information
• 204 No Content
• 205 Reset Content
• 206 Partial Content

3xx

• 300 Multiple Choices
• 301 Moved Permanently
• 302 Found
• 303 See Other
• 304 Not Modified
• 307 Temporary Redirect
• 308 Permanent Redirect

4xx

• 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
• 421 Misdirected Request
• 422 Unprocessable Content
• 423 Locked
• 424 Failed Dependency
• 425 Too Early
• 426 Upgrade Required
• 428 Precondition Required
• 429 Too Many Requests
• 431 Request Header Fields Too Large
• 451 Unavailable For Legal Reasons

5xx

• 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
• 510 Not Extended
• 511 Network Authentication Required

Socket Errors

• ECONNREFUSED
• ECONNRESET
• ETIMEDOUT
• EHOSTUNREACH
• ENETUNREACH
• EADDRINUSE
• EPIPE
• EAI_AGAIN
• ENOTCONN
• ECONNABORTED

DNS Errors

• DNS_PROBE_FINISHED_NXDOMAIN
• DNS_PROBE_FINISHED_BAD_CONFIG
• DNS Server Not Responding
• Name Resolution Failed
• Host Not Found

Browser Network Errors

• ERR_CONNECTION_REFUSED
• ERR_CONNECTION_RESET
• ERR_CONNECTION_TIMED_OUT
• ERR_NAME_NOT_RESOLVED
• ERR_NETWORK_CHANGED
• ERR_SSL_PROTOCOL_ERROR
• ERR_SSL_VERSION_OR_CIPHER_MISMATCH
• ERR_CERT_DATE_INVALID
• ERR_CERT_COMMON_NAME_INVALID
• ERR_CERT_AUTHORITY_INVALID
• ERR_PROXY_CONNECTION_FAILED
• ERR_TUNNEL_CONNECTION_FAILED
• ERR_INTERNET_DISCONNECTED

FTP Errors

• 421 Service Not Available
• 425 Can’t Open Data Connection
• 426 Connection Closed
• 450 File Busy
• 451 Local Error
• 452 Insufficient Storage
• 500 Syntax Error
• 530 Login Incorrect
• 550 File Unavailable
• 553 File Name Not Allowed

SMTP Errors

• 421 Service Not Available
• 450 Mailbox Busy
• 451 Local Error
• 452 Insufficient Storage
• 500 Syntax Error
• 501 Syntax Error in Parameters
• 535 Authentication Failed
• 550 Mailbox Unavailable
• 552 Mailbox Full
• 554 Transaction Failed

SSH Errors

• Permission Denied (PublicKey)
• Host Key Verification Failed
• Connection Refused
• Connection Timed Out
• Broken Pipe
• No Route to Host
• Network Unreachable