May 30, 2017 02:06 AM|EvenMa|LINK
In your case ,your site is run with IIS Express, you could modify the option by the following steps:
(1) In visual studio ,open menu "Tool" > "Options" .
(2) Choose "Projects and Solutions" > "Web Projects".
(3) Checked the option of "Use the 64 bit version of IIS Express for web sites and projects".
If you site had been deployed on IIS , you could refer to the following link.
(1) You could find which application pool your web application using ,right click on your web application ,choose "Manage Web Site" > "Advanced Settings…" on the menu, then could find the application pool which your web application using in the dialog.
(2) Find the application pool in application pools ,then click "Advanced Settings…".
(3) Set the option "Enable 32-bit Applications" to false.
If you have any other questions, please feel free to contact me any time.