<p>How can I determine if a remote drive has enough space for me to upload a given file using C# in .Net?</p>

Are you talking about mapping a network share to a logical drive on you computer?
If so you can use DriveInfo.
```
DriveInfo info = new DriveInfo("X:");

    info.AvailableFreeSpace;
```
DriveInfo only works with logical drives so if you are just using the full share (UNC) name I don't think the above code will work.