You could just look for DriveType.Removable
with DriveInfo.GetDrives
var removableDrives = DriveInfo.GetDrives()
.Where(x => x.DriveType == DriveType.Removable)
.Select(x => x.RootDirectory)
.ToList();
if (removableDrives.Any())
{
string myPath = Path.Combine(removableDrives[0].FullName, "Config1.txt");
}
Obviously you have to deal with the case that you have no (or multiple) removable drives, however I'll leave these details up to you.
DriveType Enumeration
Removable
The drive is a removable storage device, such as a floppy disk drive
or a USB flash drive.
DriveInfo.GetDrives Method ()
Retrieves the drive names of all logical drives on a computer
Remarks
This method retrieves all logical drive names on a computer. You can
use this information to iterate through the array and obtain
information on the drives using other DriveInfo methods and
properties. Use the IsReady property to test whether a drive is ready
because using this method on a drive that is not ready will throw a
IOException.