missing a using directive or an assembly reference

I spend 3 hours to debug this problem.

I change some element page "Friendly name", and things start to screw up when run the test remotely. Everything is working fine in local tests.

I have no choice, but the uninstall the mongodb, remove all the mongodb files, and reinstall the entire storage services (with mongodb back). And everything is working fine after that.

Compile failed: c:\Users\Administrator\AppData\Local\Temp\2\TSProjects\d3044404-1123-4459-97ff-a78e64d83e16\Please Review Project\New UI\PR-T107 Create Multiple Comments & Verify Content (Stable).tstest.cs(72,19) : error CS1061: 'Area51Project.Pages' does not contain a definition for 'Review1hIOpTZmK0' and no extension method 'Review1hIOpTZmK0' accepting a first argument of type 'Area51Project.Pages' could be found (are you missing a using directive or an assembly reference?)
c:\Users\Administrator\AppData\Local\Temp\2\TSProjects\d3044404-1123-4459-97ff-a78e64d83e16\Please Review Project\New UI\PR-T107 Create Multiple Comments & Verify Content (Stable).tstest.cs(82,19) : error CS1061: 'Area51Project.Pages' does not contain a definition for 'Review1hIOpTZmK0' and no extension method 'Review1hIOpTZmK0' accepting a first argument of type 'Area51Project.Pages' could be found (are you missing a using directive or an assembly reference?)