Import or Link mixed type data from Excel
There is an interesting post “External Data - Mixed Data Types” in Daily Dose of Excel blog, which certainly applies to Access also. If you would import (or link, or select) data from Excel spreadsheet with mixed type of data and one column has numbers and text, then Jet makes a guess of what type of column should be in resulting set. And quite often could happen that this guess is wrong. The trick is to add IMEX=1 to connection string, then all resulting columns will have text type. Read mentioned post for more info.