Knowledge Base for IT Professionals, Teachers and Astronauts
If you want to remove the preinstalled Windows 8 from a new Sony VAIO laptop you need an external USB DVD drive and a Windows 7 DVD. You can buy the LG external USB DVD drive for $40 at Best Buy, and the Windows 7 at Amazon. The first step is to turn off UEFI …
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When you click the Skype tile on the Windows 8.1 start screen the “modern” Skype application opens. It forces you to abandon your Skype user name and password and use a Microsoft account to log in. There is a way to use the regular Skype desktop application on Windows 8.1 Open the web browser and …
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In Windows Form applications the tooltip functionality is not built into the controls as in HTML objects. To add tooltip to your controls on Windows Forms Open the Windows Form in the designer Drag the ToolTip control from the Common Controls section of the Toolbox to the form. The ToolTip control will be placed at …
To display data in a DataGridView on a Windows Form Add a new form to the Win Form Application project Drag a BindingSource from the Toolbox to the form The bindingSource object appears below the form Rename the Binding Source Select the bindingSource1 object below the form Press F4 to display the Properties …
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SOAP web services that accept primitive type arguments (string, int, etc.) can be tested from a web browser. For security reasons this feature is disabled if the web browser runs on another machine. To enable testing the SOAP web services in the test environment from another machine add the following to the system.web section of …
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The Microsoft Visual Studio 2013 Entity Framework database query does not support the subtraction of two dates to calculate TimeSpan. For example the following statement will throw a runtime error: site.VisitFrequencySec < ((TimeSpan)(dtNow – site.LastVisitDate)).TotalSeconds) To solve the problem create a computed database column to calculate the difference between the dates and use the computed …
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When you get the following error message in Microsoft Visual Studio 2013 check the inner exception. System.Data.Entity.Core.EntityException was unhandled HResult=-2146233087 Message=The underlying provider failed on Open. Source=EntityFramework The inner exception gives you detailed information on the real cause of the error. Most of the time the inner exception is the following: InnerException: …
When you create a new Microsoft Visual Studio 2013 project that uses the Entity Framework you may get the following error message: The Entity Framework provider type ‘System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer’ registered in the application config file for the ADO.NET provider with invariant name ‘System.Data.SqlClient’ could not be loaded. Make sure that the assembly-qualified name is used …
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When you create a new web application in Microsoft Visual Studio 2013 the user database it creates is version 706. SQL Server 2008 can only open databases up to version 663 or earlier. To migrate the new Visual Studio 2013 databases to SQL Server 2008 script the database tables and create them again in the …
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There is a warning message in Xcode, the Apple iOS development environment that can have many different causes. Warning: Attempt to present … on … while a presentation is in progress! In my case Xcode displayed the warning because a button called the same view twice. When I deleted the action associated with the Touch …
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