c# - OleDbConnection close method taking long execution time -

        constr = string.format(constr, filepath, ishdr);         oledbconnection connexcel = new oledbconnection(constr);         oledbcommand cmdexcel = new oledbcommand();         oledbdataadapter oda = new oledbdataadapter();         datatable dt = new datatable();         cmdexcel.connection = connexcel;          //get name of first sheet         connexcel.open();         datatable dtexcelschema;         dtexcelschema =            connexcel.getoledbschematable(oledbschemaguid.tables, null);         string sheetname = dtexcelschema.rows[0]["table_name"].tostring();         connexcel.close(); 

i using above code read excel. stuck @ connexcel.close(); few seconds , move next statement. causing late processing on page. suggestions??

updating question give more details.

test case:- uploaded xls file took normal time. uploaded xlsx file halt @ connexcel.close() 25sec. uploaded xls file , halt xls also.

i have used following connection strings

for xls :- connectionstring="provider=microsoft.jet.oledb.4.0;data source={0}; extended properties='excel 8.0;hdr={1}'"

for xlsx :- connectionstring="provider=microsoft.ace.oledb.12.0;data source={0}; extended properties='excel 8.0;hdr={1}'"