debug diag log

hi all , 

first time i run the debug diag , maybe someone could help me understand what is this error :

DetailID = 3
Count: 1
Type: System.Web.HttpException
Message: Invalid file name for file monitoring: 'D:\demo\admin\Assets\Css\Kendo'. Common reasons for failure include:
- The filename is not a valid Win32 file name.
- The filename is not an absolute path.
- The filename contains wildcard characters.
- The file specified is a directory.
- Access denied.

have like 50 errors like this 

Thanks !