c# - On build Metadata file '…\Release\something.dll' could not be found in Visual Studio

1. Go to 'Solution Explorer'. Right click on Solution. Go to Properties. Go to 'Configuration Manager'. Check if the checkboxes under 'Build' are checked or not. If any or all of them are unchecked, then check them and try building again. Restart visual studio.
2. If the above solution(s) do not work, then follow sequence mentioned in step 2 above, and even if all the checkboxes are checked, uncheck them, check again and try to build again.
3. Build Order and Project Dependencies: SUPER TIPS!
   Go to 'Solution Explorer'. Right click on Solution. Go to 'Project Dependencies...'. You will see 2 tabs: 'Dependencies' and 'Build Order'.
   This build order is the one in which solution builds. Check the project dependencies and the build order to verify if some project  'project 1' which is dependent on other project 2' is trying to build before project2. 
4. Check the path of the missing .dll:
   Check the path of the missing .dll. If the path contains space or any other invalid path character, remove it and try building again.
   If this is the cause, then adjust the build order.
5. Restart VS and try building again.