Cannot obtain value of local or argument as it is not available at this instruction pointer, possibly because it has been optimized away

Question

Visual Studio 2010 kills (there is no other word) data in one of the arguments of the function in the unsafe block. What could cause this error? The following message shows

Answer 1

Go to Project Properties and under Build Make sure that the "Optimize Code" checkbox is unchecked.

Also, set the "Debug Info" dropdown to "Full" in the Advanced Options (Under Build tab).