Problem with public static byte Authenticate

database.cs line 1498

public static byte Authenticate(string UserName, string Password)
{
try
{
MySqlDataAdapter DataAdapter = new MySqlDataAdapter("SELECT * FROM `Accounts` WHERE `AccountID` = '" + UserName + "'", Connection);
DataSet DSet = new DataSet();

DataAdapter.Fill(DSet, "Account");

if (DSet != null && DSet.Tables["Account"].Rows.Count > 0) <-----1498
{
DataRow DR = DSet.Tables["Account"].Rows[0];

string Pass = (string)DR["Password"];
if (Pass == Password || Pass == "")
{
if (Pass == "")
{
MySqlCommand Command = new MySqlCommand("UPDATE `Accounts` SET `Password` = '" + Password + "' WHERE `AccountID` = '" + UserName + "'", Connection);
Command.ExecuteNonQuery();
}

uint LogonCount = (uint)DR["LogonCount"];
LogonCount++;

MySqlCommand Comm = new MySqlCommand("UPDATE `Accounts` SET `LogonCount` = " + LogonCount + " WHERE `AccountID` = '" + UserName + "'", Connection);
Comm.ExecuteNonQuery();

return Convert.ToByte((uint)DR["LogonType"]);
}
else
return 0;
}
else
return 0;
}
catch (Exception Exc) { General.WriteLine(Exc.ToString()); return 0; }
}

Not sure whats causing it, it just happens randomly and then no one can login.
i dont think its the login freeze, iv tried that already.

im using LOTF source 5017

You haven't told us what the problem is. In the future, format your code using the code tags.