The A male to A female cables at Dollar Tree can't supply
the current necessary to transfer file from most digital
cameras, power external hard drives or power a USB WiFi
adapter. They work well with a mouse or most thumb drives.

According to what I read a few months back, male-to-female A cables aren't
officially endorsed by the USB gods. Some USB devices aren't able to drive
more than the cable supplied with them. * Adding an extension might result in
erratic or non-behavior.

* Are USB cables transmission lines (as Ethernet cables are)? If so, the
length shouldn't make much difference.