If you own an external hard drive then you must be used to simply plugging it and having an autoplay window open up on your computer's screen. But would you know what to do if the computer displays the message External hard drive not recognized? This could happen due to a number of reasons, however, there are solutions to overcome this problem.
It's not uncommon to come across this problem, irrespective of the computer operating system you use. After all, computer hardware does give some trouble depending upon its use and compatibility.
The very first thing that you should try doing is disconnect the hard drive, and then reconnect it. Sometimes the computer may not recognize it at first, but will do so the next time.
This is especially true in cases when the autoplay window pops up, but the hard drive is not listed in the My Computer section (for Windows) or the Finder (for Mac). Different types of hard drives can require different actions in order to make them recognizable.
Another solution is to unplug the device and plug it into another USB port on the same machine. It could so happen that the port you first used was not functional or too slow. These are very simple solutions and in most cases they work. But in certain scenarios the problem could run deeper.
Other solutions to this problem include plugging the hard drive into another machine, reconnecting the power source of the hard drive if it has any, and reinstalling the drivers of the hard drive. Many times, once you are done reinstalling these drivers, there is a greater chance for it to start working.
Another way is to go to My Computer, right-click on it and then select 'Properties'. Here select the tab 'Hardware' and then click on 'Device Manager'.
You will see a list of peripherals that are attached to the computer, and if the external hard drive has a yellow symbol in front of it, it implies that there is something wrong with the device drivers. This is one of the best ways to understand the problem on Windows operating system.
If you are using a Mac and the aforementioned options do not work for you, you should know all about hard drive formatting. Windows OS uses two formats which are FAT32 or NTFS. Mac uses Mac OS X Journaled formats.
Windows based formats are incompatible on Mac and hence a Windows formatted hard drive will not be recognized on a Mac. You will need to reformat it on the Mac for future use. Unfortunately, this will erase all the data on the device, so you will need to ensure the backup of the same.
All these solutions should serve you well. If the problem still persists, then you can visit a computer repair store and have it sorted out.