It wasn't possible to use OLE in the current Windows 10 OS 64bit environment and that's why I switched to ODBC and it works.
I gave up using Visual Studio 2022 and switched to ACE for now because VS 2022 is really weird. I tried updating the current VS 2017 project but I couldn't select a NET Frame higher than 4.8. I created a new project and then I could select NET 6 or 7 if I would select "Windows Forms App" instead of "Windows Forms App (NET Framework)" but the toolbox is empty.
/*old code*/
string connStr = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + Datenbank + ";";
OleDbConnection conn = new OleDbConnection(connStr);
String strCommand = "SELECT * FROM Tickets WHERE [Ticket_Nummer] = @Ticket_Nummer";
OleDbDataAdapter da = new OleDbDataAdapter(strCommand, conn);
da.SelectCommand.Parameters.Add("@Ticket_Nummer", OleDbType.Integer).Value = Ticket_Nummer;
/*new code*/
string connStr = "Driver={Microsoft Access Driver (*.mdb)};"
+ "Dbq="+ Datenbank+";Uid=Admin;Pwd=;";
OdbcConnection conn = new OdbcConnection(connStr);
String strCommand = "SELECT * FROM Tickets WHERE [Ticket_Nummer] = ?";
OdbcDataAdapter da = new OdbcDataAdapter(strCommand, conn);
da.SelectCommand.Parameters.Add("@Ticket_Nummer", OdbcType.Numeric).Value = Ticket_Nummer;
/*rest code*/
DataSet DataSet = new DataSet();
da.Fill(DataSet, "TICKET");
DataTable dataTable = DataSet.Tables[0];
DataTableReader dr = new DataTableReader(dataTable);