Resolve ReferenceError: "_" is not defined. (backbone.validation-0.7.1.js#11) in Reference My Account

1. Navigate to Setup > Site Builder > SSP Applications.
2. Click on Edit for your deployed My Account SSP Application (e.g. Reference My Account, Custom My Account).
3. Check that "underscore-1.4.4.js" is added before "backbone.validation-0.7.1.js"
4. If not, swap their positions. These are the paths for underscore-1.4.4.js and backbone.validation-0.7.1.js

Web Site Hosting Files/Live Hosting Files/SSP Applications/NetSuite Inc. - My Account/Reference My Account/ssp_libraries/underscore-1.4.4.js

Web Site Hosting Files/Live Hosting Files/SSP Applications/NetSuite Inc. - My Account/Reference My Account/ssp_libraries/backbone.validation-0.7.1.js

5. Save.