If you take a look at all the calls we get here in the SMS/ConfigMgr support group, this one would have to rank right up there in popularity. What happens here is the Distribution Point (DP) share, or the DP itself, is removed but you still have packages pointing to the missing resource.
Usually you'll know this is what happened because the distmgr.log shows something like the following:
Cannot establish connection to
ANAGER 17672 (0x4508)
Error occurred. SMS_DISTRIBUTION_MANAGER 17672 (0x4508)
You'll also notice that the DP share name (or the DP) is listed in the list of available DP's for the
package and is shown as unknown. So now what do you do? Here's how you can remove those entries for the nonexistent server/share: