In this post I will discuss how to open a fire wall port in Windows 7 machine. I will use opening port for SQL Server access in your machine for inbound connections.

• Goto Start > Control Panel.

• Click on System and Security option in right pane.

  

• Now you will see options in right pane and one of them is Windows Firewall. Click on that option.

  

• Now you have details about Windows Firewall status etc. on your machine.

• Click on Advanced Settings link in left hand pane.

  

• Now you have a very elaborate user interface with very detailed status of fire wall on your machine. In left hand pane you will see option for Inbound Rules. This is what you need to click because we are about to open a port for incoming connections for your machine.

  

• You will see all the firewall port rules for incoming connections. On right side, click on New Rule link to start adding new rule for opening port in firewall.

  

• Now you will have wizard to help you add port opening rule. Since we are going to open port, select radio button for Port. For example for SQL Server you will enter port number as 1433 if you have default settings for SQL Server.

  

• Follow the wizard to add port. At one step you will get option to select what type of network will have access to this port. If you do not want the port to be open in public network then uncheck that option. It will be important if you use your machine on public WiFi networks.

  

Once you have followed these steps, you will have your port open in firewall.

Some time back I wrote an article on similar topic How to get IP address of a machine using C#. That article was written in days of .Net1.1. Since then .Net framework has come a long way. Some APIs were deprecated and a lot of new APIs were added. This post is an update on that old article. While I was working on a silverlight socket programming project, I had to deal with lot of Networking APIs. During that process I ended up writing a new method that returns me list of local IP addresses and presenting that to user to decide on what IP address they want to run socket server. Hope this post provides a quick coding tip on how you can get local IP address of your machine.

Private Function GetIPs() As StringCollection
 Dim localIP = New StringCollection()
 Dim localHostName = Dns.GetHostName()
 Dim hostEntry = Dns.GetHostEntry(localHostName)
 ' Grab all ip addesses.
 For Each ipAddr As IPAddress In hostEntry.AddressList
  localIP.Add(ipAddr.ToString())
 Next
 GetIPs = localIP
End Function

Pardon my VB.Net code. I am not very intimate with this language. You can find C# code at old article location

If you are using Verizon Wireless Broadband Access you may run into this problem some time. After you disconnect from wireless broadband and try to use LAN access or wireless network at home or work, internet explorer refuses to connect to any URL. But if you use any other browser like FireFox or Chrome, you can connect to internet. From what I have seen, VZAccess Manager adds an entry in Internet Explorer's connections options for Broadband Access. And modifies other settings in there so that Internet Explorer can only connect when you are connected to wireless broadband. To fix this problem, following the following steps.

• Launch IE
• From menus goto Tools > Internet Options > Connections tab.
• In Dial-up and Virtual Private Network settings section, you will see an entry for NationAccess-BoradbacnAccess and may be some others as well if you have other dial up connections configured on your machine. Remove these entries.
• Hit OK and then try to connect now.

Following image shows how Connections tag entries may look like before fixing it.

I have been using CISCO VPN client to connect on Windows Vista to my work for more than a year. All of a sudden I started getting following error.

I searched around to find cause and solution to this problem. It seems that a lot of people have come across this issue on Windows Vista at some point or the other. There are different solutions provided for this problem but it looks that there is no one silver bullet that kills this error. I went through process of trial and error with different solution. And found that there is one solution works most of the time.

• Open list of your Network connections from control panel
• Set the connection for VPN to Disable state.
• Now connect with VPN client.