Recently there is a problem with the computer of nearby friends, their computer can connect to the home wireless network, but the hint is restricted, do not know how to solve. At first I thought it was the password input error of the wireless network of the computer network, later confirmed is not wrong, but strange is before, how can not now, after careful questioning have not moved a computer or something, the answer is used to be a desktop wireless internet, now use this is a new notebook computer, But it turns out that the father's room desktop is still available, and from this information it can be found that the problem is probably in your filter. After landing wireless network you have found that the results of the IP filter set up to prevent others to use software to crack the net, the result I just need to add a new MAC address notebook, the result can be on. Wireless internet is the most disturbing is the network limited situation, the wireless network may connect, the signal is also very good, is not on the net. The signal on the wireless network has a yellow exclamation mark on it, but it's not on the net. In fact, this problem for the wireless network is still very common, the cause of this problem there are many, the following on a few common situations to troubleshoot wireless network can be connected, but not on the network. 1, check whether the password is wrong input wireless connection password, if the password is relatively long may be wrong password, so we recommend that you enter a password again. If possible, enter the password directly using the copy-paste method. When copying and pasting, be careful not to select irrelevant characters yo, add one or two spaces is the most common error. 2, wireless router binding MAC address in order to prevent others rub the net, many home users have set up wireless MAC address filtering, but when the computer or wireless network card replacement, it will not be on the network, so need to add a new MAC address in the router settings. 3, check service settings issues Check the computer side of the service settings, such as DHCP Client, Wirelesszero Configuration service does not start, will cause wireless network use is not normal. Where DHCP is not turned on, computers that use automatic IP allocation cannot automatically configure IP addresses. 4, check the manually assigned IP address wireless network using the manually assigned IP address and DNS address, which you need to set up in the wireless connection properties under Windows. Windows and Linux are not the same, you can not set different IP addresses for different wireless networks, so when switching between multiple wireless networks, it is easier to use a manually assigned IP. 5, wireless NIC driver incorrect This situation mostly occurs in the first time using a wireless network card, if the use of Windows 7, will normally automatically download and install the correct network card driver. But in extreme cases,, the download driver is not necessarily suitable for NIC use, so it may be necessary to download the driver from the manufacturer's homepage. 6, check the WPA patch is installed under Windows XP, need to install patches to support WPA2-PSK encryption, so if the router uses this encryption and you have not upgraded to XP SP3, please install KB893357 patch. Wireless network can connect, but not on the network of the fault check on the above steps, but may be a lot of other reasons, network adapter driver is not compatible with the possibility of Internet connection, but not on the network. Wireless internet is really a lot of problems, before a lot of people use BT3,BT4 software to break someone else's to free wireless internet access, the most easily cracked is the network WEP and WAP encryption, but wap2 cracking difficult, So the friend who uses the wireless network best chooses WAP2 network encryption way or chooses MACIP address to filter all is very safe.