D-Link Router DIR-855 User Manual

77D-Link DIR-855 User Manual
Section 5 - Connecting to a Wireless Network
Configure Wireless Security
It is recommended to enable wireless security (WPA/WPA2) on your wireless router or access point before configuring your wireless 
adapter. If you are joining an existing network, you will need to know t\
he security key or passphrase being used.
2. Highlight the wireless network (SSID) you would like to connect to 
and click Connect.
1. Open  the  Windows  Vista®  Wireless  Utility  by  right-clicking...

78D-Link DIR-855 User Manual
Section 5 - Connecting to a Wireless Network
3. Enter the same security key or passphrase that is on your router and click 
Connect.
It may take 20-30 seconds to connect to the wireless network. If the connection 
fails, please verify that the security settings are correct. The key or passphrase 
must be exactly the same as on the wireless router. 

79D-Link DIR-855 User Manual
Section 5 - Connecting to a Wireless Network
Connect Using WCN 2.0 in Windows Vista® 
The router supports Wi-Fi protection, referred to as WCN 2.0 in Windows Vista®. The following instructions for setting this up depends 
on whether you are using Windows Vista® to configure the router or third party software.        
When you first set up the router, Wi-Fi protection is disabled and unconfigured. To enjoy the benefits of Wi-Fi protection, the router 
must be both enabled and...

80D-Link DIR-855 User Manual
Section 5 - Connecting to a Wireless Network
Connect to a Wireless Network
Using Windows® XP
Windows® XP users may use the built-in wireless utility (Zero Configuration Utility). The following instructions are for Service Pack 
2 users.  If you are using another company’s utility or Windows® 2000, please refer to the user manual of your wireless adapter for 
help with connecting to a wireless network. Most utilities will have a “site survey” option similar to the Windows® XP...

81D-Link DIR-855 User Manual
Section 5 - Connecting to a Wireless Network
Configure WPA-PSK
It is recommended to enable WPA on your wireless router or access point before configuring your wireless adapter. If you are joining 
an existing network, you will need to know the WPA key being used.
2. Highlight the wireless network (SSID) you would like to connect 
to and click Connect.
1. Open  the  Windows®  XP  Wireless  Utility  by  right-clicking 
o n   t h e   w i r e l e s s   c o m p u t e r   i c o n...

82D-Link DIR-855 User Manual
Section 5 - Connecting to a Wireless Network
3. The Wireless  Network  Connection  box  will  appear.  Enter  the  WPA-PSK 
passphrase and click Connect.
It may take 20-30 seconds to connect to the wireless network. If the connection 
fails,  please  verify  that  the  WPA-PSK  settings  are  correct.  The  WPA-PSK 
passphrase must be exactly the same as on the wireless router. 

83D-Link DIR-855 User Manual
Section 6 - Troubleshooting
Troubleshooting
This chapter provides solutions to problems that can occur during the installation and operation of the DIR-855.  Read the following 
descriptions if you are having problems. The examples below are illustrated in Windows® XP.  If you have a different operating system, 
the screenshots on your computer will look similar to the following exam\
ples.
1. Why can’t I access the web-based configuration utility?
When entering the IP...

84D-Link DIR-855 User Manual
Section 6 - Troubleshooting
• Configure your Internet settings:
• Go to Start > Settings > Control Panel. Double-click the Internet Options Icon. From the Security tab, click the button 
to restore the settings to their defaults.
• Click the Connection tab and set the dial-up option to Never Dial a Connection. Click the LAN Settings button. Make 
sure nothing is checked. Click OK. 
• Go to the Advanced tab and click the button to restore these settings to their defaults. C\...

85D-Link DIR-855 User Manual
Section 6 - Troubleshooting
3. Why can’t I connect to certain sites or send and receive emails when connecting through my router? 
If you are having a problem sending or receiving email, or connecting to secure sites such as eBay, banking sites, and Hotmail, we 
suggest lowering the MTU in increments of ten (Ex. 1492, 1482, 1472, et\
c). 
Note: AOL DSL+ users must use MTU of 1400. 
To find the proper MTU Size, you’ll have to do a special ping of the destination you’re trying...

86D-Link DIR-855 User Manual
Section 6 - Troubleshooting
 
You should start at 1472 and work your way down by 10 each time. Once you get a reply, go up by 2 until you get a fragmented 
packet. Take that value and add 28 to the value to account for the various TCP/IP headers. For example, lets say that 1452 was the 
proper value, the actual MTU size would be 1480, which is the optimum fo\
r the network we’re working with (1452+28=1480). 
Once you find your MTU, you can now configure your router with the...