unable to connect to networked pc's

[fordly56]

i have multibale comupters on our network all on the same workgroup. they all are all running winxp pro, and they can all connect to the server running server 2003. but from the server, i can go to my network places, and see the other computers on the network, but when i try to connect to some of them, i get the "you don't have permissions" message.
i can go to the pc, check the settings, reboot it, and then maybe connect to it. but a day later, can't. most of the computers connect all the time. but, others are hit or miss.
all have the same settings. i have sharing enabled, quest account enabled, c: drive shared, user account shared, firewall disabled, and windows folder shared, but still can't connect to it although i can see it on the network.
someone told me it's a windows problem but didn't know what. perhaps someone here does.
would love the help.
thanks!

[MrBlack]

are all the clocks time synched?

[fordly56]

never thought about that! i'll check.

[skitzzy]

I assume all the username and passwords are the same? I know I always had issues with that on XP. I recall that all the usernames and passwords needed to be the same across all machines. Also is the option Use Simple File Sharing checked on all XP machines? Tools > View > Bottom of the list is the option.

[bmaverick]

Do any of them have "Remote Access" turned on for that workgroup or another workgroup?