For Windows only (7 and up) What OS are you using.
With no programs running, Plug in dongle. Does windows make the USB connect sound?
If no, troubleshoot your USB port.
If yes continue.
Zip SDR# into folder of your choice.
In that folder, Double click ''install-rtlsdr.bat'. MUST have access to then net as it downloads a zip file with a DLL and zadig.exe you need with SDR#.
If this completes then check that 2 extra files are in SDR# folder "rtlsdr.dll" and zadig.exe.
Run zadig and follow instructions to the letter at this page:
Setup dongle driver [rtlsdr.org wiki]
This must install successfully.
Unplug dongle from USB then reconnect to USB.
Start SDR#
Make sure your source is RTL-SDR (USB). If not select it.
Click the little gear next to the play button. Under device it should be "Generic RTL2332U OEM (0)" or use drop down box and select it. see image.
If not, driver not still not installed right.
Report back how it goes and with a bit of detail.
NOTE: If you are using Win XP you need to use the XP version of zadig