HTTP status code and definition parsing Ajax capture callback error reference
The status line contains the HTTP Version, status code, and brief descriptions corresponding to the status code. In most cases, all Response Headers except Content-Type are optional. However, Content-Type is required. It describes the MIME Type of the subsequent documents. Although most responses contain a document, some do not. For example, responses to HEAD requests will never come with the document. Many status codes are actually used to identify a failed request, and these responses do not contain documents (or only contain a brief Error Message description ).
When a user attempts to access content on a server that is running Internet Information Service (IIS) through HTTP, IIS returns a digital code indicating the status of the request. The status code can indicate whether the request is successful or not, and reveal the exact cause of the Request failure.
1xx-Information prompt
These status codes indicate temporary responses. Before receiving a regular response, the client should be prepared to receive one or more 1xx responses. 100-continue.
101-switch protocol.
2xx-success
This type of Status Code indicates that the server successfully accepts client requests.
200-OK. The client request is successful.
201-created.
202-accepted.
203-non-authoritative information.
204-NO content.
205-Reset content.
206-part of content.
3xx-redirection
The client browser must perform more operations to implement the request. For example, the browser may have to request different pages on the server or repeat the request through the proxy server.
302-the object has been moved.
304-not modified.
307-temporary redirection.
4xx-client Error
The client seems to be faulty when an error occurs. For example, the client does not provide valid authentication information for a page that does not exist in a request.
400-Incorrect request.
401-Access denied. IIS defines many different 401 errors, which indicate more specific error causes. These specific error codes are displayed in the browser but not in the IIS log:
401.1-Logon Failed.
401.2-login failed due to server configuration.
401.3-the ACL is not authorized due to resource restrictions.
401.4-filter authorization failed.
401.5-An error occurred while authorizing the ISAPI/CGI application.
401.7? The access is denied by the URL Authorization Policy on the Web server. This error code is dedicated to IIS 6.0.
403-Access prohibited: IIS defines many different 403 errors, which indicate more specific error causes:
403.1-the execution access is forbidden.
403.2-Read access is forbidden.
403.3-write access is forbidden.
403.4-require SSL.
403.5-require SSL 128.
403.6-the IP address is rejected.
403.7-client certificate required.
403.8-site access is denied.
403.9-too many users.
403.10-the configuration is invalid.
403.11-change the password.
403.12-access to the ing table is denied.
403.13-the client certificate is revoked.
403.14-reject the directory list.
403.15-the access permission of the client is exceeded.
403.16-the client certificate is untrusted or invalid.
403.17-the client certificate has expired or has not yet taken effect.
403.18-the requested URL cannot be executed in the current application pool. This error code is dedicated to IIS 6.0.
403.19-CGI cannot be executed for clients in this application pool. This error code is dedicated to IIS 6.0.
403.20-logon to Passport failed. This error code is dedicated to IIS 6.0.
404-not found.
404.0-(none )? No file or directory found.
404.1-unable to access the Web site on the requested port.
404.2-the Web service extended locking policy blocks this request.
404.3-the MIME ing policy blocks this request.
405-HTTP predicates used to access this page are not allowed (methods are not allowed)
406-the client browser does not accept the MIME type of the requested page.
407-proxy authentication is required.
412-precondition failed.
413? The Request Entity is too large.
414-the request URI is too long.
415? The media type is not supported.
416? The requested range cannot be met.
417? Execution failed.
423? An error occurred while locking.
5xx-Server Error
The server cannot complete the request because of an error.
500-internal server error.
500.12-the application is busy restarting on the Web server.
500.13-the Web server is too busy.
500.15-Direct Request to Global. asa.
500.16? Invalid UNC authorization credenunc. This error code is dedicated to IIS 6.0.
500.18? URL-authorized storage cannot be opened. This error code is dedicated to IIS 6.0.
500.100-Internal ASP error.
501-the header value specifies the unimplemented configuration.
502-the Web server received an invalid response when used as a gateway or proxy server. 502.1-CGI application timeout.
502.2-CGI application error.
503-the service is unavailable. This error code is dedicated to IIS 6.0.
504-gateway timeout.
505-the HTTP version is not supported.
Common HTTP status codes and their causes
200-successful. This status code indicates that IIS has successfully processed the request.
304-not modified. The document requested by the client is already in its cache and has not been modified since the cache. The client uses cached copies of documents instead of downloading documents from the server.
401.1-Logon Failed. The logon attempt fails, possibly because the user name or password is invalid.
401.3-the ACL is not authorized due to resource restrictions. This indicates that NTFS permission issues exist. This error may occur even if you have the relevant permissions on the file you are trying to access.
403.1-the execution access is forbidden.
The following are two common causes of this error:
You do not have sufficient execution permits. For example, if the directory permission of the ASP page to be accessed is set to "NONE", or the directory permission of the CGI script to be executed is "only allow scripts ", this error message is displayed. To modify the execution permission, right-click the directory in the Microsoft Management Console (MMC), and then click the properties and directory tabs to ensure that the appropriate execution permission is set for the content to be accessed.
You have not set the script ing of the file type you are trying to execute to identify the predicates used (for example, GET or POST ). To verify this, right-click the directory in MMC, click Properties, Directory tab, and configuration, and then verify that the script ing of the corresponding file type is set to allow the predicates to be used.
403.2-Read access is forbidden. Verify that IIS has been set to allow read access to the directory. In addition, if you are using a default file, verify that the file exists.
403.3-write access is forbidden. Verify that the IIS and NTFS permissions are set to grant write access to the directory.
403.4-require SSL. Disable the require secure channel option, or use HTTPS instead of HTTP to access this page.
403.5-require SSL 128. Disable the require 128-bit encryption option, or use a browser that supports 128-bit encryption to view the page.
403.6-the IP address is rejected. You have configured your server to deny access to your current IP address.
403.7-client certificate required. You have configured your server as a client authentication certificate, but you have not installed a valid client certificate.
403.8-site access is denied. You have set domain name restrictions for the domain you use to access the server.
403.9-too many users. The number of users connected to the server exceeds the connection limit you set.
Note: Microsoft Windows 2000 Professional and Microsoft Windows XP Professional automatically set a maximum of 10 connections on IIS. You cannot change this restriction.
403.12-access to the ing table is denied. The client certificate is required for the page to be accessed, but the user ID mapped to your client certificate has been denied access to the file.
404-not found. This error occurs because the file you are trying to access has been removed or deleted. This error also occurs if you attempt to access a file with a limited extension after installing the URLScan tool. In this case, "Rejected by URLScan" appears in the log file of the request.
500-internal server error. Many server errors may cause this error message. The Event Viewer log contains more detailed error causes. In addition, you can disable the friendly HTTP Error message to receive detailed error descriptions.
500.12-the application is restarting. This indicates that you attempt to load ASP pages When IIS restarts the application. After the page is refreshed, this information disappears. If this information appears again after the page is refreshed, it may be that the anti-virus software is scanning the Global. asa file.
500-100.ASP-ASP error. If the ASP page to be loaded contains the error code, this error message is displayed. To obtain more accurate error information, disable the friendly HTTP error message. By default, this error message is only enabled on the default Web site.
502-Gateway error. If the CGI script to be run does not return a valid HTTP header set, this error message is displayed.