The fix to this issue is to ensure that any data inserted into the MSN field is a valid email value. As such, here are the changes needed to properly validate the input to the MSN field.
1. register.asp
At approximately line#293, where you now have
Replace it by
2. Pop_profile.asp
Approximately at line# 1065 and line# 1386 (line# already including the first change), where you now have
replace it by
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