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How do I change my IP Address?
 
There are MANY methods to change your IP address.
 Some methods will work for you but may not work for someone else and 
vice versa.  We're going to cover how to change your IP address in 
Windows 2000, XP, 2003, and Vista using command prompt. 
What if I have a static IP address?
If your IP is static, then you CAN’T change it 
without contacting your  
ISP.  Although not impossible, it is very rare 
that an ISP would assign you a static IP without some sort of increased 
level of service like a business account.  However, an ISP can set a 
lengthy lease time for your IP address and make it look like you've 
assigned a static IP.  If you have a long lease time (explained in this 
article) on your IP then you may not be able to change your IP address
 without leaving your modem or router unplugged for a long period of 
time (more than 8 hours), or without cloning your MAC address, which 
I’ll explain later in this article. 
It definitely helps if you know how the IP is being assigned to you. 
You can read our DHCP definition to get a better understanding. 
What is an IP address lease time?
An IP lease time is the amount of time your ISP determines 
you’ll be assigned a particular IP. Some IP lease times could be just a 
couple of hours, where some are set to a few days, and other IP lease 
times could be set for as long as a year or more. This setting is 
completely up to your ISP. 
One of the easier methods to change your IP address is to turn off your modem/router/computer overnight. Then turn it back on the following morning. This method WILL NOT work if your ISP has a long lease time set for your IP. 
The following method will ONLY work if your computer is being assigned your external IP and not a router. 
How to determine if your computer is being assigned the external IP 
If your connection is direct to your computer and your computer gets the public IP and not a router, you can try this: 
For Windows 2000, XP, and 2003 
1. Click Start 
2. Click Run 
3. Type in cmd and hit ok (this opens a Command Prompt)  
4. Type ipconfig /release and hit enter 
5. Click Start, Control Panel, and open Network Connections 
6. Find and Right click on the active Local Area Connection and choose Properties 
7. Double-click on the Internet Protocol (TCP/IP) 
8. Click on Use the following IP address 
9. Enter a false IP like 123.123.123.123 
10. Press Tab and the Subnet Mask section will populate with default numbers 
11. Hit OK twice 
12. Right click the active Local Area Connection again and choose Properties 
13. Double-click on the Internet Protocol (TCP/IP) 
14. Choose Obtain an IP address automatically 
15. Hit OK twice 
16. Go to What Is My IP to see if you have a new IP address 
 
For Vista (Windows 7 is very similar) 
1. Click Start 
2. Click All Programs expand the Accessories menu 
3. In the Accessories menu, Right Click Command Prompt and choose Run as administrator 
4. Type ipconfig /release and hit enter 
5. Click Start, Control Panel, and open Network and 
Sharing Center. Depending on your view, you may have to click Network 
and Internet      before you see the Network and Sharing Center icon 
6. From the Tasks menu on the left, choose Manage Network Connections 
7. Find and Right click on the active Local Area 
Connection and choose Properties (If you’re hit with a UAC prompt, 
choose Continue) 
8. Double-click on Internet Protocol Version 4 (TCP/IPv4) 
9. Click on Use the following IP address 
10. Enter a false IP like 123.123.123.123 
11. Press Tab and the Subnet Mask section will populate with default numbers 
12. Hit OK twice 
13. Right click the active Local Area Connection again and choose Properties 
14. Double-click on Internet Protocol Version 4 (TCP/IPv4) 
15. Choose Obtain an IP address automatically 
16. Hit OK twice 
17. Go to What Is My IP to see if you have a new IP address 
Some people have inquired about manually 
assigning their IP address. This IS possible, but you run a very high 
risk of your ISP banning you from connecting to the internet. To 
manually change your IP, follow the steps above for your 
Operating System. In step 9 or 10, depending on your O/S, enter an IP 
similar to the one displayed in the command prompt window. For example, 
if the IP displayed in the command prompt window is 75.1.2.3, change 
yours to 75.1.2.4. You’ll also need to manually enter the Subnet, 
Gateway and DNS Server IP addresses. If the new IP you give your 
computer doesn’t work, chances are someone else on the ISP network has 
already been assigned that IP. You’ll need to move on to the next one 
and keep trying until you find an open one. Keep in mind that some ISPs 
match up your MAC or modem data to the address that’s been assigned. If 
those 2 things don’t match up, you won’t be able to connect no matter 
what. If your router gets the IP and not your computer, you’ll need to 
http in to your routers interface and manually assign the IP there. It’s
 pretty much the same method as assigning the IP to your computer. The 
method that varies is in how you reach your routers interface. You can 
get the instructions from your manufacturer’s website. 
MAC Cloning. What is a MAC address? A MAC address
 is a physical hardware address assigned to each device that has the 
capability of connecting to a network. The internet is nothing more than
 a large network. The MAC address is something that is assigned in the 
chip on the device and is not something the user can change. MAC cloning
 can only be done at your router providing it has those capabilities. 
Most ISPs assign their IPs based on the MAC address in your equipment. 
If the MAC address of your router is 00-11-22-33-44-55 and you connect 
to your ISP, the DHCP server records your MAC and assigns an IP. If you 
disconnect from the ISP, you lose your IP address. The next time you 
connect, the DHCP server sees your MAC, looks to see if it has assigned 
an IP address to you before. If it has and the lease time has not 
expired, it will most likely give you the same IP address you had before
 disconnecting and will not change your IP. 
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