Here is a huge collection of e-books offered by Microsoft.
Office & Office 365
Deployment guide for Office 2013
Microsoft Office 365 for professionals and small businesses: Help and How To
SharePoint
Explore SharePoint 2013
Deployment guide for SharePoint 2013
Test Lab Guide: eBook for SharePoint Server 2013 Intranet and Team Sites
Create a Balanced Scorecard (SharePoint Server 2010)
SharePoint Server for Business Intelligence
SQL Server
5 Tips for a Smooth SSIS Upgrade to SQL Server 2012
A Hitchiker's Guide to Microsoft StreamInsight Queries
Data Mining Extensions (DMX) Reference
Data Quality Services
High Availability Solutions
Master Data Services
Monitor and Tune for Performance
Multidimensional Expressions (MDX) Reference
SQL Server Distributed Replay
Transact-SQL Data Definition Language (DDL) Reference
XQuery Language Reference
Extracting and Loading SharePoint Data in SQL Server Integration Services
Integration Services: Extending Packages with Scripting
Multidimensional Model Programming
Optimized Bulk Loading of Data into Oracle
Planning Disaster Recovery for Microsoft SQL Server Reporting Services in SharePoint Integrated Mode
SQL Server 2012 Tutorials: Reporting Services
SQL Server 2012 Tutorials: Writing Transact-SQL Statements
SQL Server Community FAQs Manual
System Center
Cmdlet Reference for App Controller in System Center 2012 SP1
Technical umentation for System Center 2012 - Virtual Machine Manager
Visual Studio
Better Unit Testing with Microsoft Fakes
Dependency Injection with Unity
Developer's Guide to Microsoft Enterprise Library (Second Edition)
Testing for Continuous Delivery with Visual Studio 2012
Upgrade Team Foundation Server 2012: the ultimate upgrade guide
Web Development
ASP.NET Multi-Tier Windows Azure Application Using Storage Tables, Queues, and Blobs
ASP.NET Web Deployment using Visual Studio
Developing Modern Mobile Web Apps
The Entity Framework 4.0 and ASP.NET Web Forms – Getting Started
Getting Started with the Entity Framework 4.1 using ASP.NET MVC
Project Silk: Client-Side Web Development for Modern Browsers
Windows
Administrator's Guide for Microsoft Application Virtualization (App-V) 5.0
Administrator’s Guide for Microsoft BitLocker Administration and Monitoring 1.0
Administrator’s Guide for Microsoft Diagnostics and Recovery Toolset (DaRT) 7
Administrator’s Guide for Microsoft Diagnostics and Recovery Toolset (DaRT) 8.0
Administrator’s Guide for Microsoft User Experience Virtualization (UE-V) 1.0
Developing an end-to-end Windows Store app using C++ and XAML: Hilo
Developing an end-to-end Windows Store app using JavaScript: Hilo
Prism for the Windows Runtime: Developing a Windows Store business app using C#, XAML, and Prism
Programming Windows 8 Apps with HTML, CSS, and JavaScript
Windows Azure
Autoscaling Application Block and Transient Fault Handling Application Block Reference
Create Your First Application: Node.js and Windows Azure
Developing Multi-tenant Applications for the Cloud on Windows Azure (3rd Edition)
Drupal on Windows Azure
Exploring CQRS and Event Sourcing: A journey into high scalability, availability, and maintainability with Windows Azure
Migrating Data-Centric Applications to Windows Azure
Moving Applications to the Cloud on Windows Azure (3rd Edition)
Using Windows Azure Mobile Services to Cloud-Enable your iOS Apps
Using Windows Azure Mobile Services to Cloud-Enable Your Windows Phone 8 Apps
Using Windows Azure Mobile Services to Cloud-Enable your Windows Store Apps in C#
Using Windows Azure Mobile Services to Cloud-Enable Your Windows Store Apps in JavaScript
Windows Azure and SQL Database Tutorials
Windows Server
A Guide to Claims-Based Identity and Access Control, Second Edition
Introducing Windows Server 2012
TCP/IP Fundamentals for Microsoft Windows
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