In a previous article describing how to read the data from Excel file with help of C#, the end developer may face a problem of not able to read the data from a column that contains mixed data types. For e.g. if you have got a column in which the data looks like this: 125200 568585 F25363 152525 The above data will be read except for a value starting with F . This is because when we read the excel with Oledb driver , there is a " RowsToGuess " property in the registry setting which tells how many rows to scan to govern the datatype of the column. If we set that to 0, all the rows are scanned to determine the datatype. Also we need to use IMEX attribute setting in the connection string so that the data is always read in the "Text" Format. This will help in removing the problem. The following code shows how to set the IMEX setting: OleDbConnection vConn = new OleDbConnection("...