Title: Fatal error: Cannot declare class
Last modified: November 24, 2020

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# Fatal error: Cannot declare class

 *  Resolved [zontar1](https://wordpress.org/support/users/zontar1/)
 * (@zontar1)
 * [5 years, 6 months ago](https://wordpress.org/support/topic/fatal-error-cannot-declare-class-4/)
 * Hello,
 * After trying the Autoptimize plugin I returned to Fast Velocity Minify but now
   
   I get this error.
 * Fatal error: Cannot declare class MatthiasMullie\Minify\Minify, because the name
   is already in use in /var/www/html/wp-content/plugins/fast-velocity-minify/libs/
   matthiasmullie/minify/src/Minify.php on line 26
 * How do I fix this error? Is this a bug?

Viewing 2 replies - 1 through 2 (of 2 total)

 *  Plugin Author [Raul P.](https://wordpress.org/support/users/alignak/)
 * (@alignak)
 * [5 years, 6 months ago](https://wordpress.org/support/topic/fatal-error-cannot-declare-class-4/#post-13705274)
 * It means, some other plugin is also using the MatthiasMullie\Minify\Minify library.
   
   Check if you have some other minification plugin or settings and disable it.
 * Also I expect FVM 3 to be out this week and that library has been renamed, so
   there should be no more issues.
 *  Thread Starter [zontar1](https://wordpress.org/support/users/zontar1/)
 * (@zontar1)
 * [5 years, 6 months ago](https://wordpress.org/support/topic/fatal-error-cannot-declare-class-4/#post-13706926)
 * Ok thank you for a great plugin 5 stars!

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘Fatal error: Cannot declare class’ is closed to new replies.

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 * 2 replies
 * 2 participants
 * Last reply from: [zontar1](https://wordpress.org/support/users/zontar1/)
 * Last activity: [5 years, 6 months ago](https://wordpress.org/support/topic/fatal-error-cannot-declare-class-4/#post-13706926)
 * Status: resolved