Hello, i have bought the toshiba canvio 1tb (Mac) it works fine with the mac but will not work when i try to use on my HP desk

[markfletch]

Toshiba hard drive

 

[Calculagator]

It is probably formatted to use the OSX filesystem (HFS+). Windows cannot read this without a special program like http://www.catacombae.org/hfsexplorer/

If you initialize the disk from windows (erasing everything) it will be formated either FAT or NTFS and will be usable from both computers. You will not be able to use time machine, however.