Files has invalid value "<<<<<<< .mine". Illegal characters in path [Solved]

First you have to remove any characters like "<<<<<<< .mine" or similar from the file that you will see in your project Folder.

If you don't find "<<<<<<< .mine" this one then you have to search in bollow this file
.csproj.FileListAbsolute.txt

which contains a list of all the paths and recompile ...it worked for me :)