Linux – cannot remove owned file with 777 permissions

To remove one file you need write permission on the directory that contains¹ this file.

Here the permissions are dr-xr-xr-x 3 rayell pg1083760 4096 2010-10-10 10:00 . So nobody (other than root) can remove files inside this directory. The owner must use chmod first.

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^{1. There are pretty good reasons for that. By ‘removing’ a file with rm, you are in fact trying to unlink it from the directory (hardlinked copies will not be deleted).}

Another possible question is attribute

lsattr file

This command will show you attribute of the file and a file with 'i' attribute cannot be modified (and be deleted)

so check your file's attribute and remove 'i' attribute if the attribute is been set

chattr -i file