014 No longer able to set EnableViewStateMac to false.md

14: No longer able to set EnableViewStateMac to false

Scope

Major

Version Introduced

4.5.2

Source Analyzer Status

Available

Change Description

ASP.NET no longer allows developers to specify <pages enableViewStateMac="false"/> or <@Page EnableViewStateMac="false" %>. The view state message authentication code (MAC) is now enforced for all requests with embedded view state. Only apps that explicitly set the EnableViewStateMac property to false are affected.

• Quirked
• Build-time break

Recommended Action

EnableViewStateMac must be assumed to be true, and any resulting MAC errors must be resolved (as explained in this guidance, which contains multiple resolutions depending on the specifics of what is causing MAC errors).

Affected APIs

• Not detectable via API analysis

Category

ASP.NET

More information