DateTime dt = DateTime.ParseExact(\"1122010\", \"Mddyyyy\", System.Globalization.CultureInfo.CurrentCulture);
Throwing this exception: String was
I suggest using the format "MMddyyyy" and ensuring your input parameter has at least 8 characters. Example:
DateTime dt = DateTime.ParseExact("1122010".PadLeft(8, '0'), "MMddyyyy", System.Globalization.CultureInfo.CurrentCulture);
If you are using a data source with the leading 0 missing for the month, this will add it where required.