dotnet/Documentation/compatibility/sharing-session-state-with-asp_net-stateserver-requires-all-servers-in-the-web-farm-to-use-the-same-_net-framework-version.md

## Sharing session state with Asp.Net StateServer requires all servers in the web farm to use the same .NET Framework version

### Scope
Edge

### Version Introduced
4.5

### Source Analyzer Status
Planned

### Change Description

When enabling
<xref:System.Web.SessionState.SessionStateMode.StateServer?displayProperty=name>
session state, all of the servers in the given web farm must use the same
version of the .NET Framework in order for state to be properly shared.

- [ ] Quirked
- [ ] Build-time break

### Recommended Action

Be sure to upgrade .NET Framework versions on web servers that share state at
the same time.

### Affected APIs
* `F:System.Web.SessionState.SessionStateMode.StateServer`

### Category
ASP.NET

[More information](http://connect.microsoft.com/VisualStudio/feedback/details/823803/asp-net-stateserver-requests-are-not-compatible-between-4-0-and-4-5-1-versions-of-net-framework)

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