Please help us help you and fill where relevant:
LimeSurvey version: [LimeSurvey Community Edition Version 7.0.7+260729]
Own server or LimeSurvey Cloud: Own Server
Survey theme/template: Any theme
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Hi. We just upgraded from v6 to v7. All has seemed to be working well over the last two weeks. We just noticed that if we click to edit any surveys, the URL remains the same as it has always been, for example:  mySite.com/index.php/surveyAdministration/view?surveyid=123456 . However when we click on ONE of our surveys versus all of the others, the URL is different and looks like this:  mySite.com/editor/#/survey/123456 . 

Note the EDITOR in the URL. It only does it for one survey and then the screen displays "checking permissions" and then gets stuck and never advances. Even if we manually key in the syntax of the working URL, it will redirect to the EDITOR URL. I am assuming this is attempting to use the new editor vs the old? Any idea why this is redirecting to this different URL rather than using the old control panel editor like all of our other surveys? 

At the moment we cannot access this one survey as a result. We also attempted to copy it and it too produces the same results. 
Thank you for any help.