Have CNAME point to a Windows Host and access via SMB

I was trying to map \servernamesharename which would be \Web1Sharename.  Web1 would be an actual NetBIOS name and ‘ServerName’ would be a DNS CNAME to Web1.  I was getting an error.  “because a duplicate name exists on the network”

Got To:
HKEY_LOCAL_MACHINESystemCurrentControlSetServicesLanmanServerParameters

Create a new DWORD with the following details:
Value name: DisableStrictNameChecking
Data type: REG_DWORD
Radix: Decimal
Value: 1

http://support.microsoft.com/?id=281308