Conecting to a shared file access denied.

My environment is as follows.
Server 2003 domain.
Xp Pro workstations sp3

The file is being shared from a XP workstation (computerB) and I am attempting to connect with another xp workstation (computerA).

The Domain admin is able to map the shares.
Users are not.

I recieve the error whether using IP or system name.

I checks share permissions and the user has read, write, change permissions on the folder.

I am recieving the following error.
"The mapped network drive could not be created because the following error has occurred.
An Extended Error has occured."

Event Type:      Failure Audit
Event Source:      Security
Event Category:      Logon/Logoff
Event ID:      534
Date:            3/17/2011
Time:            5:04:34 AM
User:            NT AUTHORITY\SYSTEM
Computer:      ComputerB
Description:
Logon Failure:
       Reason:      The user has not been granted the requested
             logon type at this machine
       User Name:      chester
       Domain:            cheetoes
       Logon Type:      3
       Logon Process:      NtLmSsp
       Authentication Package:      MICROSOFT_AUTHENTICATION_PACKAGE_V1_0
       Workstation Name:      ComputerA
For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.



WHat more information is needed and how do I trouble shoot and resolve this issue?