iPhone : Error while trying to change any file name or add new file in project

I am getti开发者_StackOverflowng following errors while I am trying to change any file name or try to add any new file in my project.

   Error : Bad Signature;
   Fatal : index file corrupt

What should I do ?

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Remove the index with below command,

$ rm -f .git/index

then restore index to version in the last commit:

$ git reset

Or you can use lower level (plumbing) 'git read-tree' instead of 'git reset'. make a backup copy if you want, before removing index