Using Swift I got the error that my \"TableViewController\" is unreachable because it has no entry points and no runtime access via [UIStoryboard instantiateViewControllerWithId
I had same issue that to solve this problem I opened the Document Outline then realized that I have accidentally deleted the Segue between two pages.
Steps:
1) Editor> Show Document Outline document outline
2) Check the Document Outline for any copy-paste, segue error or etc. screenshot
copy-paste