Technicolor and MacOS

[#1]

I have just upgraded one of my iMacs (24 inch Early 2009, 2.66 GHz Intel Core 2 Duo) to Yosemite (10.10.1) and it no longer can gain access through Technicolor to the USB drive attached to the modem.  My Laptop (MacPro 17 inch early 2008, 2.5GHz Inter Core 2 Duo) upgraded recently to Yosemite (10.10) also now has this issue.  One of my other iMacs (Retina 5k 27 inch late 2014, 3.5GHz Intel Core i5) running Yosemite (10.10.1) is in a similar predicament.  Seems to be a Yosemite issue.
My old trusted desktop system (2004 G5 MacPro, Dual 2GHz PowerPC G5) running MacOs 10.5.8 meanwhile connects beautifully.  I haven't tried another older iMac I have which also runs 10.5.8.
Can anyone provide any advice?  Is there a Technicolor upgrade?
Thanks
Terry

[#2]

Sorry should have said I am using Technicolor TG582n FTTC Software Release 8 C.M.0.

[#3]

There is an upgrade - see http://products.plus-payh.co.uk/firmware/ but you won't be able to install it unless you have a PC lying about
However I am fairly certain the problem isn't the router firmware hence I have moved it to here

[#4]

The problem is that the router firmware doesn't support a sufficiently new version of the Windows File sharing protocol (SMB), and newer versions of OSX removed support for the older protocol. I don't think the 10.2 firmware changes that situation.
As an alternative you could enable the FTP server for content sharing and access the drive using FTP.

[#5]

This may help to explain why newer versions of the Mac OS can't access the file server in the routers.
http://appleinsider.com/articles/11/03/23/inside_mac_os_x_10_7_lion_server_apple_replaces_samba_for_...

[#6]

no, that only talks about using SMB under OS X Server, the real culprit is likely to be as ejs said OS X  defaults to SMB3.
You could try this to switch http://www.macupdate.com/app/mac/50723/smbconf

[#7]

Just came across this, I'm not a mac user myself, but would this fix the problem?
http://www.macupdate.com/app/mac/41541/smbup

[#8]

Thanks for help everyone.  I think that you are right in your combined analysis of the situation, both with the problem and the potential solution..  Looks to me to be a step too far for what I gain from having direct access to the USB drive connected to the router.  I have my G5 on all the time as a server and I can share the screen of my G5 on my iMacs and laptop in an instant.  By doing that I have access to the USB drive on the router from anywhere on my home network.
Best wishes

[#9]

Hi terryallan,
Just thinking aloud here, just in case it's the issue.
Is the firewall enabled on your Yosemite machine's?
If so, have you tried temporally disabling it to see ftp works?
Because depending on configuration's of ftp client & server, sometimes some port/s needs to be open on client machine if it's in active mode.
See http://slacksite.com/other/ftp.html