As we discussed, then you should write:
if (backplanes.Count <= 0) break;
To remove first element you can use (instead of "backplanes = backplanes-1;")
backplanes.RemoveAt(0);
for(int i=0; i< backplanes.Count; i++ )
{
}
For more:
http://msdn.microsoft.com/en-us/library/5cw9x18z.aspx[
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