I have Access .MDB file with 125 fields in one table. If I open this MDB I have seen all 125 fields. If I open the same table by OpenSource MDB Viewer I see data in 125 fields, but catalog of fields is truncated on 50 fields.

Fields list truncated

I need to open this MDB with my .NET Framework 4.8 program. I make this job by OleDb.OleDbConnection provider with this connection string

 Provider=Microsoft.Jet.OLEDB.4.0;Data Source=G:\my.mdb

Unexpectedly, I can see only first 50 fields of data. Any attempt to read by ADO.NET next field from 50 to 125 is filed.

 Input6
 at System.Data.ProviderBase.FieldNameLookup.GetOrdinal(String fieldName)
 at System.Data.OleDb.OleDbDataReader.GetOrdinal(String name)
 at System.Data.OleDb.OleDbDataReader.get_Item(String name)
 at AtiConverter.Module1._Closure$__._Lambda$__12-4(OleDbDataReader X) in G:\Projects\ATI\Access\Converter1\Converter1\AccessRead.vb:line 63
 at AtiConverter.RawSqlQuery.RawSqlQuery[T](OleDbConnection Connection, String SqlQuery, Func`2 RowMapperFunc, Boolean NeedPrint) in G:\Projects\ATI\Access\Converter1\Converter1\RawSqlQuery.vb:line 23

I use ordinary Win 11 with last update.