Symantec Backup Exec 12

i have to install symantec backup in computer A as a PC_BACKUP and i have computer B as a PC_SERVER. i have a problem in Symantec Backup Exec Remote Installation.

 

activity was i doing is like below :

 

right click in "Windows Remote Agents" --> add remote computer-->microsoft windows network-->"PC_SERVER"

 

in "Remote Computer Logon Credentials"  have information :

 

server name  \\PC_SERVER

 

user name    : xxxxxxx [ i add an administrator user in PC_SERVER]

password     : xxxxxxxx [as like as password administrator user in PC_SERVER]

domain         : PC_SERVER [because my OS server is Win XP SP 2, and i not use domain, but i use a workgroup]

 

after  i press OK, symantec  give a message "attempt to connect server \\PC_SERVER failed with following error : access is denied"

 

whats wrong with my step, if a have a mistake ???

 

for more information, i was edited group policy in PC_SERVER. i was enabled an option "allow remote administration exception' and turn off windows firewall.

 

please give my a solution. thanks