C# - Error When Executing A Stored Proc

I am attempting to execute a stored proc in asp.net in the code behind. The parameter I am trying to pass is strErrorMessage that contains a value of "The transport failed to connect to the server.; ". The error message when the query gets executed is: The incoming tabular data stream (TDS) remote procedure call (RPC) protocol stream is incorrect. Parameter 1 ("@errMessage"): Data type 0xE7 has an invalid data length or metadata length. Update with code

try
{
...
...
...
}
catch (Exception ex)
{
ClientScript.RegisterStartupScript(GetType(), "alert", "alert('Email was not sent - " + ex.Message + "');", true);
string strMessage = ex.Message;
string strStackTrace = ex.StackTrace;
strMessage = strMessage.Replace("
", "; ");
strMessage = strMessage.Replace(" ", "");
strStackTrace = strStackTrace.Replace("
", "; ");
strStackTrace = strStackTrace.Replace(" ", "");
AppErrorLog(strMessage, strStackTrace);
return false;
}
protected void AppErrorLog(string strErrorMessage, string strErrorStackTrace)
{
SqlConnection conErrLog = new SqlConnection(strConn);
string sql = "usp_AppErrorLog_AddRecord";
SqlCommand cmdErrLog = new SqlCommand(sql, conErrLog);
conErrLog.Open();
try
{
cmdErrLog.CommandType = CommandType.StoredProcedure;
cmdErrLog.Parameters.Add(new SqlParameter("@errMessage", SqlDbType.NVarChar, 8000));
cmdErrLog.Parameters["@errMessage"].Value = strErrorMessage;
cmdErrLog.Parameters.Add(new SqlParameter("@errStackTrace", SqlDbType.NVarChar, 8000));
cmdErrLog.Parameters["@errStackTrace"].Value = strErrorStackTrace;
cmdErrLog.Parameters.Add(new SqlParameter("@userID", SqlDbType.VarChar, 12));
cmdErrLog.Parameters["@userID"].Value = User.Identity.Name;
SqlDataAdapter ada = new SqlDataAdapter(cmdErrLog);
cmdErrLog.ExecuteNonQuery();
}
catch(Exception e)
{
ClientScript.RegisterStartupScript(GetType(), "alert", "alert('AppErrorLog - " + e.Message + "');", true);
}
finally
{
conErrLog.Close();
}
}

The column datatype in the table is nvarchar(MAX).