I am trying to run a python script which uses a binary file (xFiles.bin.addr_patched) created by a postlinker. However, I am getting this error. File "abc.py", line 74, in ParseCmd shutil.copy(gOptions.inputX, gWorkingXFile) File "/usr/lib/python2.6/shutil.py", line 89, in copy copymode(src, dst) File "/usr/lib/python2.6/shutil.py", line 66, in copymode os.chmod(dst, mode) OSError: [Errno 1] Operation not permitted: 'myPath/xFiles.bin.addr_patched' When I checked the permissions of this xFiles.bin, by ls-l, it shows that -rwxrwxrwx 1 nobody nogroup I presume the error is because this file was created by some other application, the python script I am running does not have access to it. Since I am beginner wrt ubuntu, I don't really know how to fix it. Any suggestions on how to fix this? SOLVED: As one of the answers Suggested : chown username:groupname file name fixes this issue