HTTP Error 403.9-Access prohibited: too many connected users

First, understand what is the number of IIS connections (instant connections)
The number of IIS connections refers to the number of concurrent requests in several cases: (this example uses the number of allowed instant connections)

A. the user downloads your files at a single point and is disconnected normally after completion. These connections are calculated in an instant. That is to say, the VM with 10 connections can be instantly downloaded at 10 points at the same time.

B. When a user opens your page, even if the user stays on the page and does not send any request to the server, a connection will be occupied within 90 seconds after the user opens a page, that is to say, for websites with 10 connections, you can open 10 pages for different users in 90 seconds.

C. In the case of B above, the user continues to open other pages of the same website. The number of online users is calculated based on the 90 s after the last click (Send request) of the user, in the 90 s, no matter how you click (including opening a new window), it is still a connection.

D. When an IFRAME exists in your page, you need to connect multiple frames! This means that the user requests multiple pages to the server at the same time.

E. When the user opens the page and closes the browser normally, the user's connections will be cleared immediately.

F. When an image in a Web page you make exists as a URL Connection (such as a http://123.com/image.gif. Each image URL viewer's computer must send a new request to the server. Therefore, the number of connections in use increases.

G. Links between websites.

H. If there is a downloaded file in the space! If you use thunder software, each thread represents an online connection, which occupies a lot of connection resources.

 

HTTP Error 403.9 on XP-Access prohibited: too many connected users Solution

We know that IIS allows up to 10 clients to connect to Windows 2000 Professional edition or Windows XP Professional Edition operating system. This connection restriction does not exist in Windows 2000 Server Edition or Windows 2003 Server Edition operating system. Microsoft provides metaedit, a tool for managing IIS. metaedit works on Windows NT4.0 and Windows 2000. I found that metaedit works normally on Windows XP. In addition, metaedit can only manage IIS of version ii4.0, iis5.0, or later. The following uses this tool to break through the connection restrictions of the IIS client of Windows XP Professional Edition:
First, you need to download metaedit from the following address. If you have the latest version, you can download the latest version.
Http://download.microsoft.com/download/iis50/Utility/5.0/NT45/EN-US/MtaEdt22.exe
Then, execute mtaedt22.exe and follow the wizard prompts to complete metaedit installation.
Finally, set the client connection limit parameter in metaedit.
After installing metaeditProgramClick metaedit 2.2 Under Group Administrative Tools to run. A window is displayed:
Expand the tree to Lm \ W3SVC on the left of the window, click the w3svc folder, and select the maxconnections item in the list on the right. Double-click the item and a dialog box is displayed:
In the final data text box, the default value is 10, which is the maximum number of client connections set by default in Windows XP Professional IIS. Now you can change this default value. I will change it to 10000. Next, I double-click maxconnections and check it in front of secure! Click OK to check it!

Finally, the appendix describes the common reasons why ie cannot open a webpage and how to solve it.

Author: jowhale Source: China tutorial Network
I. Network Settings
This is because you need to manually specify the IP address, gateway, and DNS server connection mode, and use the proxy server to access the Internet. Carefully check the computer's network settings.

Ii. DNS server problems
When ie cannot browse the Web page, try the IP address first. If yes, it should be a DNS problem, the DNS problem may be caused by an error in obtaining the DNS when the network is connected or a problem with the DNS server itself. In this case, you can manually specify the DNS Service (the address can be the DNS server address provided by your local ISP, you can also use the DNS server address in other places .) In the network properties, (Control Panel-network and dial-up connections-local connection-right-click Properties-TCP/IP protocol-properties-use the following DNS server address ). Different ISPs have different DNS addresses. Sometimes it is a problem with the vro or Nic and cannot be connected to the DNS Service of the ISP. In this case, you can turn the vro off for a while or reset the vro.
Another possibility is that the local DNS cache is faulty. To speed up Website access, the system automatically saves a website that has been accessed and obtained an IP address to the local DNS Cache. Once the website is accessed again, then, the IP address of the website is not directly retrieved from the local DNS Cache through the DNS server for access. Therefore, if a problem occurs in the local DNS cache, the website cannot be accessed. You can execute ipconfig/flushdns in "run" to recreate the local DNS cache.

Iii. Problems with IE browser
When the IE Browser fails, browsing is naturally affected, or the IE is maliciously modified or damaged, leading to the inability to browse the Web page. At this time, you can try to use "Huangshan ierepair expert" to fix the problem (it is recommended to fix it in safe mode), or re-run IE (for example, if you encounter a problem that cannot be re-installed, refer: appendix 1 solves the problem of re-installing ie)

Iv. Network Firewall Problems
If the network firewall is improperly set, for example, the security level is too high, ie is accidentally put into the blocked access list, or the firewall policy is incorrect, you can try to check the policy, reduce the firewall security level, or directly turn it off and try to restore the normal state.

V. network protocol and NIC Driver Problems
IE cannot be browsed. It may be caused by network protocol (especially TCP/IP Protocol) or network card driver damage. You can try to re-drive the network card and network protocol.

Vi. Hosts file Problems
The modification of the hosts file also causes abnormal browsing. The solution is to clear the content in the hosts file.

7. System File problems
when the system files related to IE are replaced or damaged, the normal use of IE may be affected. In this case, you can use the SFC command to fix the problem, the Win98 system can execute SFC in "run" and then scan; and win2000/XP/2003 execute SFC/scannow in "run" to try to fix it.
when only ie cannot browse the Web page, and QQ can be accessed, it is often caused by Winsock. DLL, wsock32.dll, or wsock. vxD (VxD only exists in the Win9x system) and other files are damaged or lost. Winsock is an important part of the TCP/IP protocol. Generally, the TCP/IP protocol must be reinstalled. However, XP began to integrate the TCP/IP protocol, so it cannot be simply uninstalled and reinstalled like 98. You can use the netsh command to reset the TCP/IP protocol, restore it to the status when the operating system is installed for the first time. The procedure is as follows:
click "start running", enter the "cmd" command in the running dialog box, and enter "netsh int IP reset C: \ resetlog.txtlogs: The resetlog.txt file is used to record the command execution result. This parameter must be specified. The complete path of the specified log file is "C: \ resetlog.txt ". The result of executing this command is the same as deleting and re-installing the TCP/IP protocol.
tips: The netsh command is a command-line-based scripting tool. You can use this command to configure and monitor Windows systems. In addition, it provides an interactive network shell program interface, for the format of the netsh command, see the Help File (enter "netsh /?" ).
the second solution is to repair the above files. Win9x uses SFC to re-extract the above files. Win2000/XP/2003 uses the SFC/scannow command to repair the files, if SFC/scannow cannot be used to fix the problem, you can try winsockfix, a repair tool released on the Internet. You can search and download it online.

VIII. Real-time Monitoring of anti-virus software
This is not often seen, but sometimes it is related to real-time monitoring, because the real-time monitoring of anti-virus software is now added to the monitoring of web content. For example, kv2005 will cause IE to fail to browse the Web page on some machines (many friends have met it). The specific performance of kv2005 is as long as web page monitoring is enabled, after the Internet connection is started for about 20 minutes, ie will be unable to browse the Web page. If kv2005's web page monitoring is turned off, everything will return to normal. After a thorough reinstallation of kv2005, it will not be able to solve the problem. Although this problem does not occur for every sub-machine that installs kv2005, after all, the sub-systems of each machine are different and the installed programs are different. If IE cannot browse the webpage, check anti-virus software.

IX. Application Management Service Problems
When the web page cannot be opened only on QQ, You can restart it. However, even if it is restarted, after opening 7 to 8 web pages, you can only go to QQ. Sometimes, China Telecom often allows you to disable the application management service. The specific cause is unknown.

10. Virus Infection
This often occurs when you open ie. In the lower-left dialog box of the IE interface, the system prompts that the webpage is being opened, but the webpage does not respond for a long time. Check the process in the Task Manager (enter the method, place the mouse on the taskbar, right-click the Task Manager-process) to see how the CPU usage is. If it is 100%, you can be sure, if you want to run other programs, the virus is infected. Check which process occupies CPU resources greedily. after finding it, you 'd better record the name and click "end". If it cannot be completed, you need to start to secure mode to delete the stuff and enter the Registry. (method: start-run, enter Regedit) in the Registry dialog box, click Edit-search, enter the program name, find it, right-click to delete it, And then perform several searches, it can often be completely deleted.
There are a lot of viruses. When anti-virus software is powerless, the only way is to manually delete them.

11. The second-level link cannot be opened.
note that the second-level link cannot be opened on the homepage of a website, the solution is to re-register the following DLL file:
enter in start-run:
regsvr32 shdocvw. DLL
regsvr32 shell32.dll (do not enter this command First)
regsvr32 oleaut32.dll
regsvr32 actxprxy. DLL
regsvr32 mshtml. DLL
regsvr32 urlmon. DLL
regsvr32 msjava. DLL
regsvr32 browseui. DLL
Note: Press ENTER for each entry. The second command does not need to be input. After these commands are input, restart Windows. If it is invalid, enter the second command again.