Ok, I never post help here cause I am not a technical person unless your talking about cars (or sometimes motorbikes:D) but some help would be greatly appreciated.
This may take a while to explain, sorry...
I downloaded Audacity and used it to record a few tracks(using the mic line in) then decided to delete it as I would be getting Pro Tracks soon. I deleted it. Saved one of the files as an MP3 and carried on my merry way.
When I downloaded Pro Tracks I followed the instructions to the book(both online and the instruction manual). I couldn't get it to work, there was no signal being received.
I tried every Line-in I could. These included different coloured sockets. One Pink, one blue. I also have a green socket and a black socket, they are both used for speakers. I also have a yellow one, that is labeled Digital Out. I also tried the USB as a friend did when he owned the program. None worked. Though I have an old USB system that may well not be quick enough to handle that sort of signal.
Eventually I downloaded Audacity again after PX said I may have lost the correct drivers when I deleted Audacity and/or downloaded Pro Tracks.
But, no matter what I selected as my line in on Audacity, I got the same result. Nothing.
PX also mentioned a program called Kristal. So, in the vein hope that Audacity was just being a pain in the bum I downloaded this.
So here I am, I have been through three different programs and still when I press record, after following all the instructions I can, I have no input signal, and there for nothing for the program to record.
At the moment I am running my guitar in to a Digitech RPx400 effects pedal running two line outs. One to the amp and one plugged into the back of my computer using a 5mm to 3.5mm adapter with a 3.5mm jack plug to 3.5mm jack plug (double ended lead) going between the adapter and the computer. This is the same set up I used with audacity originally.
I want to get some tracks on to Bandamp, considering I have been a member for about three years (previously Kimoki and then Apache) and still ahve no music up here to show for it.
Any help will be hugely appreciated,
KI

well, as far as I can tell from here, there are a few things that could be wrong.

1) your cable is screwed, or your 3.5 mm adaptor is screwed (this can happen). are you using the right kind of cables? if you go from a mono 5 mm jack into a stereo 3.5 mm via the adaptor, your signal might be cancelled. You would need a stereo cable (2xmono jack going from the stereo pair on your RPx400 into 1xstereo 3.5 mm plug, adaptors placed at either the outputs of your effects 3.5 to 5, or stereo adaptor 5 to 3.5 at the cpu input).

2) wrong output setting on your RPx400. I've gone through the manual (it can be found on this page: http://www.digitech.com/literature.htm) and on pages 23 and 24 there's something about output settings and signal routing. It could be that your signal IS going to your amp, but NOT to your computer. Don't know ofcourse... just trying to help here.

3) your soundcard is screwed. it could be that you accidentally destroyed (blew up) your input in a previous attempt to get sound into your computer. Bad news, it would require replacement.

I can't do much from over here. All I can suggest is going over your soundcard settings to check if maybe the input is being muted or set to 0 Volume level, and it could also be that there are programs claiming priority over the use of your soundcard, so your audio program can't produce any sound anymore. For instance, if I run Cubase, other programs (Skype, itunes, the flash player on bandamp) can't produce any sound at all.

You should also check your sound drivers... go get asio4all and investigate properly... Make sure your audio program is set to make use of the right driver (audio programs do not select the right drivers automatically) Selecting drivers can usually be done via "Preferences" somewhere in a menu

If none of this helps then I don't know... I would need pictures of your rig and screenshots from all your menus in order see things deeper... And all in all I'm not a tech wiz so I doubt that'll be any better...

Good luck...

If it is a wondows based pc,

   go to your device manager, and check your audio devices, and see if you have any exclamation marks ( ! ) on anything.. or question marks ( ? ).. this means there is a driver issue, I accidently deleted my srivers once too... if there are, then you need to check the properties of the item(s) and choose update driver... allow wondows to search for you, it should find them, as they aren't really deleted, windows just doesn't know any better....

   after that , it should work fine....

             Jim K