Keep Losing Connectivity

[Frink]

Hello all. Thanks for providing this great forum, here is my situation. I have a 5 computer office network (1 server, 4 workstations all hard wired). One of the workstations continually looses connection to the sql database on the server causing an error on the workstation. Sometimes I can restart the program and re-connect but other times I have to reboot the workstation to get it to reconnect with the sql server. I have tried eliminating the obvious (bad wiring) by disconnecting the Ethernet cable from the workstation and running it on the network using a USB wireless adapter but this did not help. This is the only workstation that has the problem. I am looking for suggestions as to what to do next. I know the wireless signal is good as I have 2 wireless laptops that I use from time to time and neither one of them has this problem.
Here is the hardware configuration:
CenturyLink ISP DSL Modem
Netgear GS108 8 port Gigabit switch
Workstation: HP Compaq DC7900 - Windows 7 Professional 64-bit

One thing I have not tried - I have some workstations coming directly off the router and some from the Gigabit switch. Should I have everything running from the switch?

Any other troubleshooting help will be greatly appreciated.

 

[Joe C]

Can you switch out workstations? That will determine if it's something within your network or the workstation itself

 

[1etherer]

Can you check and post your event viewer logs so we can see what errors are showing up

 

[Frink]

I have attached some errors and warnings found in the event viewer as requested. I have swapped out the workstation and still got the error.
I have switched the cabling so that all stations are connected to the Gigabit switch which is the only connection going to the router. This seems to have helped slightly but I still got the error once today however I was able to re-establish connection to the sql server by opening up Google Chrome and going onto the internet. So I think that should help with a solution in that I lose connectivity to the sql server on the network, but if I open Chrome and go onto the internet, the connection to my internal LAN is re-established. What should be my next step?

Event viewer errors:

1. 
   Event filter with query "SELECT * FROM __InstanceModificationEvent WITHIN 60 WHERE TargetInstance ISA "Win32_Processor" AND TargetInstance.LoadPercentage > 99" could not be reactivated in namespace "//./root/CIMV2" because of error 0x80041003. Events cannot be delivered through this filter until the problem is corrected.
2. The IP address lease 192.168.0.157 for the Network Card with network address 0x0025B3105C63 has been denied by the DHCP server 192.168.0.1 (The DHCP Server sent a DHCPNACK message).
3. The ICS_IPV6 was unable to allocate  bytes of memory. This may indicate that the system is low on virtual memory, or that the memory manager has encountered an internal error.
4. Session "Homegroup Log" failed to start with the following error: 0xC0000035
5. Event filter with query "SELECT * FROM __InstanceModificationEvent WITHIN 60 WHERE TargetInstance ISA "Win32_Processor" AND TargetInstance.LoadPercentage > 99" could not be reactivated in namespace "//./root/CIMV2" because of error 0x80041003. Events cannot be delivered through this filter until the problem is corrected.
6. Warning 3/3/2015 3:56:08 PM SharedAccess_NAT 34005 None
   The ICS_IPV6 was unable to allocate  bytes of memory. This may indicate that the system is low on virtual memory, or that the memory manager has encountered an internal error.
7. Installing printer driver MINOLTA-QMS PagePro 1250W failed, error code 0x0, HRESULT 0x80070705. See the event user data for context information.
   
8. Installing printer driver Brother MFC-7340 Printer failed, error code 0x0, HRESULT 0x80070705. See the event user data for context information
9. event user data for context information
10. Event filter with query "SELECT * FROM __InstanceModificationEvent WITHIN 60 WHERE TargetInstance ISA "Win32_Processor" AND TargetInstance.LoadPercentage > 99" could not be reactivated in namespace "//./root/CIMV2" because of error 0x80041003. Events cannot be delivered through this filter until the problem is corrected

 

[carnageX]

Make sure that the "Power saving" feature that allows Windows to turn off the network card to save power is disabled.

 

[Frink]

Power saving feature is turned-off, that was one of the first things I checked when this problem started - thanks for your reply.

 

[pokemaster]

Have you tried a good ole fashion reboot on the router? Or have you tried connecting the workstation directly to your router? It could always be a bad port on the switch.