Hello everyone,
Can anyone tell me why Eagle failed to autoroute my PCB then we can see obvious solutions?
Most likely your DRC rules specify a minimum clearance between pads and tracks which make routing the trace up and between those 2 pads (The one Through-holr on the left and the smd pad on the right) impossible.
You can check by manually routing the trace that way and then execute a DRC check.
Hope this helps,
Thanks,
Guido
Thanks man, it helped, I didn't noticed that clearance was too small. 
I'm never satisfied with the autorouter, it doesn't even give supply nets wider traces,
and just doesn't do anything sensible on a crowded board in my experience.
When you assign the supply nets to a new net-class with specific (wider) minimum trace-width the autoroute takes that into account, if i remember correctly.
The autorouter needs a bit of cleanup indeed, but for quick layouts it does the job reasonably ok i think.
Cheers,
Guido
In this case, it looks like the pads of that transistor might be too close to the edge of the board for the autorouter to consider them "reachable." (DRC's "Distance" between copper and dimension.)
it doesn't even give supply nets wider traces,
As DeepZ says, it will if you put your supply nets in a different class: you can specify different width, via size, and clearance.
Yes, Edit:Net Classes to define different widths. Then right click on a signal on the schematic, Properties, and select the Net Class to use.