Suddenly: Mac Mini will not connect to network anymore

[vivmacMini]

I'm a 'casual' mac user for more than 4 years now. I use PCs side by side and the mac is generally my 'leisure' comp - for DVDs, Music and the internet.

I'm currently using a Mac Mini with a 20" cinematic display.
Specs:
Currently on OS ver 10.6.2
Processor: 1.83 ghz, intel, core 2 duo
1 GB 667 Mhz DDR2 SDRAM [more specs at the end of this message]

I have a password protected, wi-fi network at home with a linksys WRT610N router.

The problem started VERY arbitarily. For some reason my mac just stopped connecting to the network one fine day. At the time i was still on OS "Tiger".

It would do one of the following:
1. NOT detect my wireless network

2. when it did would request for the password but would not connect even if I typed in the correct one. (to make sure it was not a password issue, I disabled it, changed passwords etc… still nothing).

3. I kept getting this message: “could not connect to the server because the name or password is not correct”

I made sure the following was NOT the issue by contacting the ISP:

1. It's NOT an ISP issue.
2. It’s NOT an IP address, DNS issue. (but in all fairness, the technical assistance are not that mac savvy)
3. It's NOT an issue of the network range (is it?) [I use my laptop from exactly the same position without any problems].

At this point out of pure frustration I bought Snow Leopard and upgraded my OS. The same problem continued. The other day when my head was ready to explode I took it right near the router and set it up and it was working!! (at this point i quickly upgraded to the os to ver 10.6.2)

Surely enough, when I took it back to my usual working place, it stopped again! So it seems like it could be a range issue.

These days, the Mac mini occasionally detects my network, connects and only loads like half a page. And then disconnects. But a majority of the time does not even detect the network. The Airport Icon on the status bar shows a network as well from time to time but doesn’t load any pages, even when connected. In other words; cannot connect to the internet.

Here’s my issue:
The mac mini was connecting JUST FINE right from the start, where it was. Then one day stopped.
Could there be a problem with the inbuilt Airport? Can it be rectified via a range expander/ something? Is it something to do with the new router I installed?
How do I get it to work from my desk, where it used to work just fine?
Here are all the specs that seem relevant. You could always ask for more, but please be specific on where to find them as I’m not a power user.

Machine Specs:

Currently on OS ver 10.6.2
Processor: 1.83 ghz, intel, core 2 duo
1 GB 667 Mhz DDR2 SDRAM

My airport settings:


Airport:


Software Versions:
Menu Extra: 6.0 (600.22)
configd plug-in: 6.1 (610.2)
System Profiler: 6.0 (600.9)
Network Preference: 6.0 (600.22)
AirPort Utility: 5.4.2 (542.23)
IO80211 Family: 3.1 (310.6)
Interfaces:
en1:
Card Type: AirPort Extreme (0x168C, 0x86)
Firmware Version: Atheros 5424: 2.0.19.4
Locale: ETSI
Country Code:
Supported PHY Modes: 802.11 a/b/g
Supported Channels: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 36, 40, 44, 48, 52, 56, 60, 64, 100, 104, 108, 112, 116, 120, 124, 128, 132, 136, 140, 149, 153, 157, 161, 165
Status: Connected
Current Network Information:
linksys:
PHY Mode: 802.11g
BSSID: (blacked out)
Channel: 1
Network Type: Infrastructure
Security: WPA Personal
Signal / Noise: -82 dBm / -96 dBm
Transmit Rate: 18

Firewall Settings:

Mode: Allow all incoming connections
Firewall Logging: No
Stealth Mode: No


Locations:

Automatic:

Active Location: Yes
Services:
AirPort:
Type: IEEE80211
BSD Device Name: en1
Hardware (MAC) Address: (blacked out)
IPv4:
Addresses: (blacked out)
Configuration Method: Manual
Router: (blacked out)
Subnet Masks: (blacked out)
IPv6:
Configuration Method: Automatic
DNS:
Search Domains:
Server Addresses: (blacked out)
Proxies:
Proxy Configuration Method: 2
FTP Passive Mode: Yes
IEEE80211:
Allow Net Creation: Yes
Disconnect on Logout: Yes
InterferenceRobustness: 1
Join Mode: Automatic
JoinModeFallback: Prompt
MAC Address: (blacked out)
PowerEnabled: 1
PreferredNetworks:
SecurityType: WPA Personal
SSID_STR: linksys
Unique Network ID: (blacked out)
Unique Password ID: (blacked out)
RememberRecentNetworks: 1
RequireAdminIBSS: 0
RequireAdminNetworkChange: 0
RequireAdminPowerToggle: 0

Bluetooth PAN:
Type: Ethernet
BSD Device Name: (blacked out)
AppleTalk:
Configuration Method: Node
Proxies:
FTP Passive Mode: Yes
Bluetooth DUN:
Type: PPP
IPv4:
Configuration Method: PPP
IPv6:
Configuration Method: Automatic
Proxies:
Proxy Configuration Method: 2
Exclude Simple Hostnames: No
FTP Passive Mode: Yes
Auto Discovery Enabled: No
PPP:
ACSP Enabled: No
Display Terminal Window: No
Redial Count: 1
Redial Enabled: Yes
Redial Interval: 5
Use Terminal Script: No
Dial on Demand: No
Disconnect on Fast User Switch: Yes
Disconnect on Idle: Yes
Disconnect on Idle Timer: 600
Disconnect on Logout: Yes
Disconnect on Sleep: Yes
Idle Reminder: No
Idle Reminder Time: 1800
IPCP Compression VJ: Yes
LCP Echo Enabled: No
LCP Echo Failure: 4
LCP Echo Interval: 10
Log File: /var/log/ppp.log
Verbose Logging: No
Ethernet:
Type: Ethernet
BSD Device Name: en0
Hardware (MAC) Address: (blacked out)
Proxies:
FTP Proxy Enabled: No
FTP Passive Mode: Yes
Gopher Proxy Enabled: No
HTTP Proxy Enabled: No
HTTPS Proxy Enabled: No
RTSP Proxy Enabled: No
SOCKS Proxy Enabled: No
FireWire:
Type: FireWire
BSD Device Name: fw0
Hardware (MAC) Address: (blacked out)
IPv4:
Configuration Method: DHCP
IPv6:
Configuration Method: Automatic
Proxies:
Proxy Configuration Method: 2
Exclude Simple Hostnames: No
FTP Passive Mode: Yes
Auto Discovery Enabled: No



Would APPRECIATE ANY help! I love this machine and it's frustrating me for close to a month now! PLEASEEE HELP!!!