Using edquota to set users limits the command displays the error.
edquota updates all quota files that are on a mounted filesystem. So, a directory named quotas causes it to fail.
In one of the mounted filesystems, there is a directory named quotas. To fix the problem, move the directory off the mounted filesystem, rename it, or delete it.
For example: If you have /usr/quotas/old_info The directory /usr/quotas is going to cause edquota to fail. Either move /usr/quotas to /usr/old_quotas or delete the directory.