Are you wondering to simply download a video or audio clip, or you simply need to download some of your software or files where the speed of. The Internet Download Manager serial number is technically a product key and not a serial number but many developers use the two terms. IDM, or Internet Download Manager, is one of the top-rated download Once you register the app with a working IDM serial number, you get. There are many download managers on the internet these days but as we all know IDM is The Best. Internet Download Manager aka IDM is a. I have purchased IDM but still get the following message: "Internet Download Manager has been registered with a fake Serial Number or the Serial Number has. Internet Download Manager (IDM) is a popular download manager for Windows. of IDM in order to stop it from showing the fake serial number error message.