RPC server unavailable

All,
i have written an ssis package that is designed to do the following:
1. load a list of servers from a management sql server table
2. store this into an ADO recordset
3. hand the ADO recordset off to a child package that in turn will
4. dymanically grab servernames and execute a WMI task to query the win23_logicaldisk table and store this in a dataset
5. dataset is handed to a for each loop and a data insert is made back to a management server table
The reason for the Child package is that it was one of the suggestions that I found on forum discussions to resolve the problem that I am still facing. I am recieving an error of "RPC server not available" when dymanically assign the servername to the connection string property of the WMI connection using an expression.Error: 0xC002F304 at WMI Data Reader Task, WMI Data Reader Task: An error occurred with the following error message: "The RPC server is unavailable. (Exception from HRESULT: 0x800706BA)".
I have researched this extensively and have verified that connectivity and communications are open, the rpc, rpc locator and wmi services are running. I even receive this meessage when executing this code against my local machine that is running the ssis package!
Any insight would be greatly appreciated in resolving this.
Thanks,
Steve

Thanks for all of the input on a really generic error. The Server admins here installed the most recent round of patches from MS and rebooted the servers as part of their maint procedures. Since then the problem has gone away. I am looking to track down which or how many played a part with WMI and or SSIS.
Thanks again