Network shares in Windows 7: What am I doing wrong?

I bought the extreme 6th gen and it's working rather well however I'm running into issues trying to map network share in windows.

I have a Seagate Slim 500gb bus powered external drive hooked up to the USB port on the back of extreme. There are 2 partitions both formatted for hfs, one for time machine and one for copying files.

While in mountain lion, the share works fine. I've run time machine several times and it seems all is good. However under windows it's a different story. I will map a share, I.e. \\devicename\partitionname and then it will prompt for login details. I have a device password setup, so it's the name I gave the APE and the password. However I will almost always get an error saying that "x: refers to a location that is no longer available" error.

However, if I update the APE then the network share operates fine after it restarts. Also, if I unplug the drive then plug it back in after getting the error that seems to fix it as well,

Under osx there are no issues, so I don't know why this is happening under windows only, either my desktop or laptop. Login and workgroup credentials are correct.

So is this a drive issue? Does the APE not like bus powered USB drives? Perhaps my Seagate slim is going to sleep and won't wake up unless I restart the APE. Can this be confirmed because I'm having a heck of time looking up this issue anywhere else, but surely I can be the only one running into this. Thanks.