Fatal Error: Cannot redeclare

I’m getting the following error when trying to upload a new file to replace a current one. The error shows up before I have the option to choose a new file. The error only occurs for some users (contributors, but not admin).

Fatal error: Cannot redeclare emr_menu() (previously declared in /home/ibpos/subdomains/staff.imperialbeverage.com/wp-content/plugins/enable-media-replace/enable-media-replace.php:38) in /home/ibpos/subdomains/staff.imperialbeverage.com/wp-content/plugins/enable-media-replace/enable-media-replace.php on line 39