Can't access shares after installing SP1 for Server 2008

Just finished installing SP1 for Server 2008 R2, all went fine other than i can't access any shares using a UNC. When using \server from clients or on the server i get the following message;

Windows cannot access \\ntserver

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Error Code: 0x80070002
The System cannot find the file specified.

I've also tried with the FQDN and the ip and i get the same message. I've disabled the firewalls on the server and client and still have the issue.

EDIT: also found these in the event logs, unsure if they are related;

The WinRM service failed to create the following SPNs: WSMAN/NTSERVER.school.local; WSMAN/NTSERVER. 

Additional Data The error received was 8344: %%8344.

User Action The SPNs can be created by an administrator using setspn.exe utility.

The winlogon notification subscriber <GPClient> took 97 second(s) to handle the notification event (CreateSession).  

I'm lost at what to try now!

Have a look at this page

• Open Regedit "HKEY LOCAL_MACHINE\SYSTEM \CurrentControISet\Control\NetworkProvider\Order"

• The "ProviderOrder" Key has just one value for the "hgfs"

• Validated with another server having the same configuration the Key above and the information found were different:

• The Key "ProvideOrder" contains: "vmhgfs,hgfs,RDPNP,LanmanWorkstation"

• Copied the value from this server to Issued Server.