This isn't the first time I've had this problem and the last time I had it, I didn't note down how I fixed it. I just spent the last hour or so looking for solutions to this online and to my surprise, nowhere actually has an answer.
My external hard drive would randomly disconnect for just under a second then reconnect. When searching online, I found someone suggesting that the USB port doesn't have enough power to it to power the hard drive and suggested unplugging all non-essential USB devices. I didn't think it would solve it but I tried it anyway but to no avail. Here's the things I've tried:
-remove the hard drive from the device manager so Windows re-installs the drivers
-unplugging all USB items besides the HDD so no other USB items were plugged in.
-tried different USB ports
-tried the HDD on different computers (it works on others with no problems)
-looked for a powersave setting to make sure Windows isn't turning it off due to inactivity (couldn't find any option for it)
This is quite annoying as I'm trying to watch some of my old home videos I have saved on it and it keeps disconnecting in the middle of one.
Windows XP Pro SP2
Freecom 250GB External Hard Drive (not sure of specific model number. Bought in 2005)
If I've missed out any information, just ask.