Netgear Switch will not 'see' GBIC module

We have 2 FSM726 switches linking 2 offices via a fibre cable. The network went down and the problem seems to be down to one of the switches. It previously worked fine for 6 months. The fibre has been checked and is currently back up running on old kit.

 The web based menu on switch A does not show any GBIC modules plugged in. We have changed the port config from Auto to GBIC amongst other methods to get it to work.
Eventually we had the switch replaced but the replacement switch does exactly the same thing.

Switch B does indicate a GBIC module is installed (The port shows as Blue for 'Training' on the web based config). To confuse matters, we have also just discovered that Switch B shows the GBIC port as Blue even if no module is installed.

Any ideas would be greatly appreciated.
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

please check switches firmware.
please try to check if gbic is fine ( you can take two switches and two gbic and try to connect them with fiber cord)
even more, when you insert gbic into port, you should be able to see red light coming from "transmit" hole, when looking directly into gbic.
If you can see the light, that means gbic is working and is powered. Then you can check the second gbic in the same way and if both are working, try to connect them with patch cable. the line should come up.

Btw, in case of a long line (between two buildings) you also should be able to see red light coming from one of the strands, if the other end is connected to an active gbic.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
cybis1Author Commented:
One of the GBIC modules does indeed have no light showing on the transmit side. We are awaiting confirmation from Netgear that the module itself is indeed dead.
ok, please update, when you get any info from netgear
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Switches / Hubs

From novice to tech pro — start learning today.