Unhandled exception occurred in Silverlight Applications in SharePoint 2010

"unhandled exception occurred in Silverlight Applications".This is error where we frequently get when we try to create any template selecting "more options" from site settings.This solution can be solved easily by going to Central Admin->Web Applications ->General Settings.Then your general settings web page security validation will be in on as below image,You just turn it to "off" else if it is "Off" turn it to "On"

sharepoint 2010 an unexpected error has occurred

When We come across this kind of errors ,To know the reason for this error we need to follow the steps.

->Open IIS as Administrator and select web application in which your site is existed
->Right click the web application and select explore
->Now open the web-config file in notepad and type callstack .Set callstack to false if is true else if callstack is true set it as false
->And search for customerror mode and set it to off if it is off else if customerror is off set it as on

"New" Web Application Icon in Disabled Mode

Reason
Not opening the IE in Central admin.

Solution:
Right Click the I.E on below Task bar ->And Right click on Internet Explorer option->Run As Administrator

Getting Blank page instead of Central Admin after installing SharePoint 2010 in Windows 7

Reason:
By default, some of the authentication providers may not be installed in Windows 7 machine (inside IIS). You can check the list of authentication providers by double click on the central administration site in IIS. See the sample screenshot below.

If you double click in the "Authentication" open for central admin when you opened IIS you cannot see the below authentication mechanisms:

1. Windows Authentication
2. Basic Authentication
3. Digest Authentication

Solution:
To add these authentication mechanisms in IIS, open the Command Prompt and type the below command. Then, wait for 2 minutes.

Command

start /w pkgmgr /iu:IIS-WebServerRole;IIS-WebServer;IIS-CommonHttpFeatures;IIS-StaticContent;IIS-DefaultDocument;IIS-DirectoryBrowsing;IIS-HttpErrors;IIS-ApplicationDevelopment;IIS-ASPNET;IIS-NetFxExtensibility;IIS-ISAPIExtensions;IIS-ISAPIFilter;IIS-HealthAndDiagnostics;IIS-HttpLogging;IIS-LoggingLibraries;IIS-RequestMonitor;IIS-HttpTracing;IIS-CustomLogging;IIS-ManagementScriptingTools;IIS-Security;IIS-BasicAuthentication;IIS-WindowsAuthentication;IIS-DigestAuthentication;IIS-RequestFiltering;IIS-Performance;IIS-HttpCompressionStatic;IIS-HttpCompressionDynamic;IIS-WebServerManagementTools;IIS-ManagementConsole;IIS-IIS6ManagementCompatibility;IIS-Metabase;IIS-WMICompatibility;WAS-WindowsActivationService;WAS-ProcessModel;WAS-NetFxEnvironment;WAS-ConfigurationAPI;WCF-HTTP-Activation;WCF-NonHTTP-Activation

Number validation for asp text box:

SharePoint 2010 Bussniess Connectivity Services

Bar Code Integration in SharePoint 2010 Lists