1xx – Informational
These HTTP status codes indicate a provisional response. The client computer receives one or more 1xx responses before the client computer receives a regular response.

IIS 7.0 uses the following informational HTTP status codes:

• 100 – Continue.
• 101 – Switching protocols.

2xx – Success
These HTTP status codes indicate that the server successfully accepted the request.

IIS 7.0 uses the following success HTTP status codes:

• 200 – OK. The client request has succeeded.
• 201 – Created.
• 202 – Accepted.
• 203 – Nonauthoritative information.
• 204 – No content.
• 205 – Reset content.
• 206 – Partial content.

3xx – Redirection

These HTTP status codes indicate that the client browser must take more action to fulfill the request. For example, the client browser may have to request a different page on the server. Or, the client browser may have to repeat the request by using a proxy server.

IIS 7.0 uses the following redirection HTTP status codes:

• 301 – Moved permanently.
• 302 – Object moved.
• 304 – Not modified.
• 307 – Temporary redirect.

4xx – Client error
These HTTP status codes indicate that an error occurred and that the client browser appears to be at fault. For example, the client browser may have requested a page that does not exist. Or, the client browser may not have provided valid authentication information.

IIS 7.0 uses the following client error HTTP status codes:

• 400 – Bad request.
• 401 – Access denied.

IIS 7.0 defines several HTTP status codes that indicate a more specific cause of a 401 error. The following specific HTTP status codes are displayed in the client browser but are not displayed in the IIS log: • 401.1 – Logon failed.
• 401.2 – Logon failed due to server configuration.
• 401.3 – Unauthorized due to ACL on resource.
• 401.4 – Authorization failed by filter.
• 401.5 – Authorization failed by ISAPI/CGI application.

• 403 – Forbidden.

IIS 7.0 defines the following HTTP status codes that indicate a more specific cause of a 403 error:

• 403.1 – Execute access forbidden.
• 403.2 – Read access forbidden.
• 403.3 – Write access forbidden.
• 403.4 – SSL required.
• 403.5 – SSL 128 required.
• 403.6 – IP address rejected.
• 403.7 – Client certificate required.
• 403.8 – Site access denied.
• 403.12 – Mapper denied access.
• 403.13 – Client certificate revoked.
• 403.14 – Directory listing denied.
• 403.16 – Client certificate is untrusted or invalid.
• 403.17 – Client certificate has expired or is not yet valid.
• 403.18 – Cannot execute requested URL in the current application pool.
• 403.19 – Cannot execute CGI applications for the client in this application pool.

• 404 – Not found.

IIS 7.0 defines the following HTTP status codes that indicate a more specific cause of a 404 error:

• 404.0 – Not found.
• 404.2 – ISAPI or CGI restriction.
• 404.3 – MIME type restriction.
• 404.4 – No handler configured.
• 404.5 – Denied by request filtering configuration.
• 404.6 – Verb denied.
• 404.7 – File extension denied.
• 404.8 – Hidden namespace.
• 404.9 – File attribute hidden.
• 404.10 – Request header too long.
• 404.11 – Request contains double escape sequence.
• 404.12 – Request contains high-bit characters.
• 404.13 – Content length too large.
• 404.14 – Request URL too long.
• 404.15 – Query string too long.

• 405 – Invalid verb.
• 406 – Client browser does not accept the MIME type of the requested page.
• 408 – Request timed out.
• 412 – Precondition failed.

5xx – Server error
These HTTP status codes indicate that the server cannot complete the request because the server encounters an error.

IIS 7.0 uses the following server error HTTP status codes:

• 500 – Internal server error.

IIS 7.0 defines the following HTTP status codes that indicate a more specific cause of a 500 error:

• 500.0 – Module or ISAPI error occurred.
• 500.11 – Application is shutting down on the Web server.
• 500.12 – Application is busy restarting on the Web server.
• 500.13 – Web server is too busy.
• 500.15 – Direct requests for Global.asax are not allowed.
• 500.19 – Configuration data is invalid.
• 500.21 – Module not recognized.
• 500.100 – Internal ASP error.

• 501 – Header values specify a configuration that is not implemented.
• 502 – Web server received an invalid response while acting as a gateway or proxy.

IIS 7.0 defines the following HTTP status codes that indicate a more specific cause of a 502 error:

• 502.1 – CGI application timeout.
• 502.2 – Bad gateway.

• 503 – Service unavailable.

IIS 7.0 defines the following HTTP status codes that indicate a more specific cause of a 503 error:

• 503.0 – Application pool unavailable.
• 503.2 – Concurrent request limit exceeded

Para informações mais detalhadas e erros traduzidos, visite: http://support.microsoft.com/kb/943891