请教一个连接sqlserver数据库连接错误的解决方法

webconfig里是这样写的
<?xml version="1.0" encoding="Windows-1252"?>
<configuration>
<system.web>
<!-- DYNAMIC DEBUG COMPILATION
Set compilation debug="true" to enable ASPX debugging. Otherwise, setting this value to
false will improve runtime performance of this application.
Set compilation debug="true" to insert debugging symbols (.pdb information)
into the compiled page. Because this creates a larger file that executes
more slowly, you should set this value to true only when debugging and to
false at all other times. For more information, refer to the documentation about
debugging ASP .NET files.
-->
<compilation defaultLanguage="c#" debug="true" />
<!-- CUSTOM ERROR MESSAGES
Set customError mode values to control the display of user-friendly
error messages to users instead of error details (including a stack trace):

"On" Always display custom (friendly) messages
"Off" Always display detailed ASP.NET error information.
"RemoteOnly" Display custom (friendly) messages only to users not running
on the local Web server. This setting is recommended for security purposes, so
that you do not display application detail information to remote clients.
-->
<customErrors mode="RemoteOnly" />
<!-- AUTHENTICATION
This section sets the authentication policies of the application. Possible modes are "Windows", "Forms",
"Passport" and "None"
-->
<authentication mode="Windows" />
<!-- APPLICATION-LEVEL TRACE LOGGING
Application-level tracing enables trace log output for every page within an application.
Set trace enabled="true" to enable application trace logging. If pageOutput="true", the
trace information will be displayed at the bottom of each page. Otherwise, you can view the
application trace log by browsing the "trace.axd" page from your web application
root.
-->
<trace enabled="false" requestLimit="10" pageOutput="false" traceMode="SortByTime" localOnly="true" />
<!-- SESSION STATE SETTINGS
By default ASP .NET uses cookies to identify which requests belong to a particular session.
If cookies are not available, a session can be tracked by adding a session identifier to the URL.
To disable cookies, set sessionState cookieless="true".
-->
<sessionState mode="InProc" stateConnectionString="tcpip=127.0.0.1:42424" sqlConnectionString="data source=127.0.0.1;user id=sa;password=" cookieless="false" timeout="20" />
<!-- GLOBALIZATION
This section sets the globalization settings of the application.
-->
<globalization requestEncoding="utf-8" responseEncoding="utf-8" />
</system.web>
<appSettings>
<!-- User application and configured property settings go here.-->
<!-- Example: <add key="settingName" value="settingValue"/> -->
<add key="Session["ConnStr"].ToString ()" value="" />
</appSettings>
</configuration>
我现在想连接内网的192.168.1.106这台数据库我把data source=127.0.0.1改为192.168.1.106为什么会有错误（在192.168.1.106这台能运行）