Invalid attempt to read when no data is present

You have to call DataReader.Read to fetch the result:

SqlDataReader dr = cmd10.ExecuteReader();
if (dr.Read()) 
{
    // read data for first record here
}

DataReader.Read() returns a bool indicating if there are more blocks of data to read, so if you have more than 1 result, you can do:

while (dr.Read()) 
{
    // read data for each record here
}

I would check to see if the SqlDataReader has rows returned first:

SqlDataReader dr = cmd10.ExecuteReader();
if (dr.HasRows)
{
   ...
}

You have to call dr.Read() before attempting to read any data. That method will return false if there is nothing to read.

I just had this error, I was calling dr.NextResult() instead of dr.Read().

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