hard drive appears multiple times in network

[Zaphod]

Hi. First time poster. My hard drives show up on other network machines multiple times, like this: d, d~1, d~2, d~3, etc. Why is this happening and how can I stop it?

My home network contains both Windows 7 and Windows 8.1 computers.

I am guessing that this issue may be a simple one. My apologies if it has been asked before. Though I've searched for an answer around the web, I'm honestly not even sure what key words to look for.

Thanks for any help.