Currently Being ModeratedNov 26, 2013 9:48 PM (in response to Cartoonguy)
Is this Mavericks? When you say it was working ok.. was that on previous OS?
What OS are you on?
Use the internal disk of the TC. There is a good chance the USB drive is refusing to spin up.. that is why it has lost the connection. USB are often unreliable on the TC. The exact cause is not known. But do you have a powered USB hub on it.. even if the USB is powered .. it can still require a powered hub.
What model TC is this?
What firmware level?
Currently Being ModeratedNov 26, 2013 9:53 PM (in response to LaPastenague)
Sorry, still on 10.8. Have not changed my system. The internal disk of the TC is ony 500gb, so I need the external and was led to believe that using it with an external drive would be fine, which it has been, but now this. If it's true that external is the issue, then wonder why it worked just fine for months.
Currently Being ModeratedNov 26, 2013 10:07 PM (in response to Cartoonguy)
If it's true that external is the issue, then wonder why it worked just fine for months.
So do I believe me.
A 500GB TC is old.. and is near EOL unless you have replaced its power supply.
When you attempt to backup does the external drive spin up?? If not, force it to spin up by disconnecting and reconnecting it. If it works once spinning but fails the next time.. use a powered usb hub.. I can promise you the power supply in the TC will be on its last legs. If it still fails to spin up.. there is either a fault in the external drive.. that also happens.. plug the external into the computer and test it or the TC can no longer sustain the load.
It also could be firmware.. if you recently upgraded a Gen1 TC to 7.6.4 downgrade it to 7.5.2 as it is hugely more reliable on those old models.
If you are hard wiring to the TC to do backups to an external drive.. you may be pleasantly surprised to realise the same backup to the USB drive plugged directly into your computer will go at between 2-4times the speed. In fact even USB2 disk on the computer is faster for backup than the internal disk in the TC.
It is also hugely more reliable.
Currently Being ModeratedNov 27, 2013 10:30 PM (in response to LaPastenague)
I am surprised that power supplies have such a limited life. I thought they were things that just worked for years. I mean, no moving parts, right? Anyway, I thought I was being clever by having the drive connected to the USB port, but I am going back to just having it directly connected. One reason I had it on the TC was so that it was hidden in the basement, for extra security, but I have now locked it to my desk with a cable. Much better plugged in directly. No issues and much faster. It's a firewire 800 drive too, so I was kind of frustrated that it was only being used for USB. So thanks for your suggestion.
Currently Being ModeratedNov 27, 2013 11:12 PM (in response to Cartoonguy)
Apple blundered with the Gen1 and Gen2 TC. .they ran too hot and the power supply lasted exactly what it could be expected to when the TC exceeded the rating of the power supply.. It was deliberate to prevent using the fan.
And many other posts.
eg. 89 pages of this one. https://discussions.apple.com/thread/2129872?threadID=2129872&tstart=0&messageID =10361895#10361895