Login failed for user (null)

I am creating a Data Web Form using the Data Form Wizard.
After configuring a valid connection to a SQL Server on my network, I receive the following error when trying to run the page: "Login failed for user '(null)'. Reason: Not associated with a trusted SQL Server connection."
Any ideas?

Thanks,
MarkYou need to put a proper user id and password in your connection string? Or you haven't filled out the properties properly to do the click and drag method.|||Kay -
Thanks for the response.
I initially configured the connection to use Windows Authentication. Since this didn't work, I entered my username and password using SQL Authentication. Neither seems to work. Now, I'm thinking it has something to do with not having the ASPNET username set up as having access to the SQL database.
Does this make sense?

Mark|||Did you try using IUSR_machinename?|||Jake -
What exactly is IUSR_machinename?
Where would I reference this in my connection string?

Thanks,
Mark|||Are you doing this on an Intranet or are you using a webhost?

IUSR_machinename is an anonymous internet user set up by IIS.|||I am attaching to my localhost for testing purposes.
If I attach to a SQL database on my local machine, I have no problems with the login.
If I try attaching to a database on any other server, I receive the error.

Mark|||Here's my connection string in my web.config

 <appSettings>
<add key="connString" value="server=66.24.255.01;pwd=Jeckel;uid=Jake;database=JakeJeck" />
 </appSettings>

What does your connection string look like?|||Jake -
I don't have an <appSettings> tag within my web.config file.
I added one using your example, but receive an error about an unrecognizable configuration section.
Where else could my connection string be located?

Thanks,
Mark|||Your entire web.config could look something like this:

<?xml version="1.0" encoding="utf-8" ?>
<configuration
 <appSettings>
<add key="connString" value="server=69.56.xxx.xxx;uid=xxx;pwd=xxx;database=JakeJeck"/>
</appSettings
 <system.web>
 <!-- DYNAMIC DEBUG COMPILATION
 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="vb" debug="true" /
 <!-- CUSTOM ERROR MESSAGES
 Set customErrors mode="On" or "RemoteOnly" to enable custom error messages, "Off" to disable.
 Add <error> tags for each of the errors you want to handle.
 -->
 <customErrors mode="RemoteOnly" /
 <!-- AUTHENTICATION
 This section sets the authentication policies of the application. Possible modes are "Windows",
 "Forms", "Passport" and "None"
 -->
 <authentication mode="Forms" /
 <!-- AUTHORIZATION
 This section sets the authorization policies of the application. You can allow or deny access
 to application resources by user or role. Wildcards: "*" mean everyone, "?" means anonymous
 (unauthenticated) users.
 -->
 <authorization>
 <allow users="*" /> <!-- Allow all users --
 <!-- <allow users="[comma separated list of users]"
 roles="[comma separated list of roles]"/>
 <deny users="[comma separated list of users]"
 roles="[comma separated list of roles]"/>
 -->
 </authorization
 <!-- 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
</configuration>

Then you simply access connString and you have your connection information available.sql