Server not showing up in Windows Explorer

We have a small peer-to-peer network server in our office - 5 work stations (Win 7 Pro), two networked printers and a WAP.
Somedays, when opening Windows Explorer or the "Network" icon on the desktop, any mapped drives on the server are visible but the server itself is not.  This seems to happen randomly on different workstations.  Somedays, the server is completely visible from the work stations, but other days, not at all.

(by the way, the server is still running Win XP Pro with two hard drives set up in an RAID 1/ mirroring configuration.)
Also, we do not use a domain.   Our network name is just our company name - a single word.
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On the server, make sure the NIC is now using Power Saving as in the following Picture:
As the Windows XP computer is acting as server it's probably best to set this computer as master browser.

Can you do the following on the Windows XP computer.
Open the registry editor via: Click Start |Run... |regedit
Go to:
Create or modify REG_SZ entry: MaintainServerList
Change the value to: Yes

Go to:
Create a new REG_SZ entry: IsDomainMaster
Change the value to: True

Click Start |Run... |services.msc
Go the "Computer Browser" service and make sure it's set to Automatic.
Start or Restart the "Computer Browser" service.
deroodeSystems AdministratorCommented:
If you do not see the the server show up in the network by itself, can you find it by typing \\server in the address bar of Windows Explorer? If so, create a shortcut on you pc that points to \\server, maybe even in your startup programs.
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is your server on DHCP, would set it as static IP, and do all the clients have the same workgroup name?
other machines may have some third-party firewall that blocki netbios

try nbtstat -a "IPADDRESS or HOSTNAME" from the workstations to see what resolves. if no reply then try disabling local firewall.
TimLaLAuthor Commented:
It turned out to be an issue with our router.
All computers could see the internet - outside the network - but no one could access anything "in house".
After much testing, grinding of teeth, etc, a new router was purchased, configured and everything started working again.
Thanks for all the advice.

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TimLaLAuthor Commented:
As stated - it turned out to be a hardware issue.   The other suggestions helped in that a couple of items were new to me.
regarding static IP addresses - we do have our server and our multifunciton machine (printer-scanner-copier-fax) both with static addressess.  All else are dynamic.
Thanks very much for closing the question like this, appreciated.
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Windows Networking

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