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Network copying not working due to persistent "insufficient privileges" errors

When transferring files between two computers on a local network, occasionally the system will not have enough privileges to complete the transfer.

CNET staff
4 min read

When transferring files between two computers on a local network, occasionally the system will not have enough privileges to complete the transfer.

When transferring files between two computers on a local network, occasionally the system will not have enough privileges to complete the transfer.

Apple Discussion poster "Thomas Kranz1" writes:

"I am suddenly getting this message when I try to copy a file from my new MacBook Pro to my PowerBook running 10.4.9. 'You may need to enter the name and password for an administrator on this computer to change the item named [file I am trying to transfer] (stop, continue). I hit continue and get the error message: 'The item [that I am transferring] contains one or more items you do not have permission to read. Do you want to copy the items you are allowed to read?' I say continue and get the error: 'The operation cannot be completed because you do not have sufficient privileges for some of the items.' My network was working fine until today. I can copy fine to all other computers on my network. But not this one."

When OS X transfers data between computers, you first log into the remote system and mount a readable or writable sharepoint from the remote system. Then when you transfer files they should be given ownership and permissions based on the account you're using on the remote computer (not the current computer). This ensures you can access the files anytime and from anywhere as long as you use the same credentials to log into the computer containing them.

When problems with permissions in file transfers occur, you should first check your sharepoints to ensure the account you are using has read-and-write access to the share. To do this, open the "Sharing" system preferences and select the "File Sharing" service. Then ensure the sharepoint is listed in the "Shared Folders" list and then give the username you're logging in with both "Read & Write" permissions. If you are logging in from a PC, then click the "Options" button and enable "Share files and folders using SMB" and then select the account you wish to use to log in. Clicking "Done" should allow you to log into the system using the specified credentials.

If the system keeps presenting insufficient privileges errors even after supplying appropriate credentials, the problem may be with how the computer is authenticating the account being used. For network directory authentication, OS X uses a "Universally Unique Identifier" or "UUID" number to identify user accounts, and if there is a problem with the UUID not matching, you may still be able to log in locally to the remote computer but may have permissions problems when using the same credentials remotely. Apple started implementing network directories that use UUIDs in OS X 10.3, and in 10.5 they're required, since Apple changed from the NetInfo authentication technologies to "Open Directory," which is built for network directory authentication and implements UUIDs.

In OS X 10.5, you can change the UUID for your account by going to the "Accounts" system preferences and clicking the lock to authenticate. Then right-click (options-click) your account name and select "Advanced Options." Then click the "Create New" button next to the UUID field, and a new number will be generated. This should be done on the computer that you cannot properly connect to, and not on the computer you are connecting from. All this will do is provide a new identifier for your account when you are logging in remotely, and should clear problems with authentication and permissions mismatches.

For people having problems with copying files to a 10.4 machine, it may help to ensure ownership on the shared resource is properly set. To do this, launch the terminal and type the following command, followed by a single space:

sudo chown -R `id -un`

NOTE: The command uses "grave accent" marks (`), which is the character under the "tilde" next to the "1", and not apostrophes or single-quotes.

After this has been typed (with the space following it), drag the shared folder to the terminal and the full path to the folder should complete. Then press enter and supply your password to complete the command. When this has been run, try copying the files again.

About UUIDs

UUIDs are a set of four or five grouped segments of random alphanumeric characters (specifically, hexadecimal numbers, 0 through 9, and "a" through "f") that are formed using an algorithm that assumes uniqueness. There are several versions of UUIDs, each basing their uniqueness algorithm on different things, such as the computer's MAC address. In OS X 10.5, UUID version 4 is used, which is based on random number generators and not a specific algorithm (SHA1, MAC addresses, or MD5). The idea with UUIDs is that the possible combinations are so vast that it would be nearly impossible to randomly generate the same number for two items (accounts, devices, etc) in the same situation. A description in this Wikipedia article outlines the scope of the UUID uniqueness well, stating that in order to generate the number of UUIDs available in a 16-byte, 128-bit UUID number, it would take generating "1 trillion UUIDs every nanosecond for 10 billion years". Basically, this means you shouldn't worry about two of these numbers randomly being the same.

Resources

  • Thomas Kranz1
  • Wikipedia article
  • More from Late-Breakers