.WSP File Extension

SharePoint Solution File

A WSP file is a package used by Microsoft SharePoint, an enterprise-level document and content management system. It stands for "Windows SharePoint Services Package" and contains a solution that can be deployed to a SharePoint environment. These solutions are custom components, such as websites, features, or web parts, that extend the functionality of a company's SharePoint site.

WSP files were introduced alongside Windows SharePoint Services (which later evolved into SharePoint Foundation), with their format becoming standardized around 2003-2007 when SharePoint began gaining widespread enterprise adoption. The format was created to simplify the deployment and management of custom SharePoint components.

WSP files are essentially CAB format archives (a Microsoft compression format) with a special structure that SharePoint can recognize and process. They can contain:

• Web pages and templates
• Site definitions
• Features and web parts
• Configuration files
• Code assemblies (.dll files)
• Resource files like images and CSS

How WSP Files Are Used

SharePoint administrators and developers use WSP files to:

• Deploy custom SharePoint solutions across servers in a farm
• Add new functionality to existing SharePoint installations
• Distribute and install SharePoint components in a standardized way
• Package multiple related components together for simpler deployment

The deployment process typically involves adding the solution to a SharePoint configuration database and then deploying it to the appropriate web application or site collection.

Creating WSP Files

Developers can create WSP files using:

• Microsoft Visual Studio with the "Visual Studio extensions for Windows SharePoint Services" or more recent SharePoint development tools
• The Makecab.exe command-line utility to manually package the components
• Third-party SharePoint development tools

How to Open .WSP as SharePoint Solution File

Since WSP files are compressed archives, you can:

1. Rename the file extension from .wsp to .cab
2. Open it using Windows Explorer or any archive tool that supports CAB files (like 7-Zip)
3. Browse the contents to view the individual files inside

However, to properly view the functionality of a WSP file, you need to deploy it to a SharePoint environment.

Deployment Commands

To work with WSP files in a SharePoint environment, administrators use PowerShell commands or the older STSADM utility:

Using STSADM (older method):

• Add to solution store: stsadm -o addsolution file.wsp
• Deploy to servers: stsadm -o deploysolution file.wsp

Using PowerShell (modern method):

• Add to solution store: Add-SPSolution -LiteralPath c:\path\to\file.wsp
• Deploy: Install-SPSolution -Identity file.wsp -WebApplication http://sitename -GACDeployment

How to Convert an WSP File

WSP files can be converted to other formats, though the process depends on what you're trying to achieve:

• To standard CAB/ZIP archives: Simply rename the extension and extract using appropriate tools
• To newer SharePoint package formats: For SharePoint Online/modern SharePoint, WSP solutions are being replaced by SharePoint Framework (SPFx) packages, and conversion typically requires redevelopment
• To standalone web applications: The components would need to be extracted and potentially rewritten for a different platform

No direct automated conversion exists for transforming a WSP file into a completely different application format, as the contents are specifically designed for SharePoint environments.

Compatibility

WSP files are primarily associated with on-premises SharePoint installations (SharePoint Server). With the move to SharePoint Online and modern SharePoint experiences, Microsoft has been transitioning away from WSP-based solutions toward SharePoint Framework (SPFx) packages and add-ins, which use different packaging methods.

Applications That Open WSP Files

Windows Apps for WSP Files:

• Microsoft SharePoint Paid
• Microsoft Visual Studio Free+

macOS Apps for WSP Files:

• Microsoft Visual Studio Free+