1. Open Bentley Map and assign a GCS to match that of the .prj file. Reference or import the Shapefile data into the Design File.
2. Create a Named Range in the Excel sheet that contains the data you want to Join. The Scope should be the range of cells – either select the range, or specify Workbook. Save the .xls file with this new Named Range.
3. Create an ODBC Data Source (DSN) for Bentley Map to use to connect to this data. Select the Excel .xls file that you created in the previous step.
4. The next step is to create a VRT file that will relate the ODBC DSN to a Feature for Bentley Map to use. The Help file is the best place to start for this, look in the Interoperability chapter, under the Importing an ODBC Data Source heading.
5. Start by copying & pasting the code section into a text file. In our case we do not need the <GeometryField> tag, you can remove that. Change the Geometry Type to wkbPolygon.
6. Right-click on the Feature in Map Manager that represents the Shapefile data. Select the Join… menu item.
7. Select the .VRT file created in the previous step using the New File Source… drop-down list in the Right-side Properties.
8. Select the desired rows from the right and left-side properties columns, GIS_ID2 in this case
9. Select the Add Selected Left/Right Properties button to add the new the definition to the Join Column list
10. Select the OK button to create the Join
Browse for New Source File…
11. Verify that the join was successful by selecting a building in the design file with the Analyze XFM Feature command. The additional details will be prefaced with the Layer Name defined in the VRT file.
This is Microsoft Windows capabilities. You can run it from the Windows start menu or C:\Windows\SysWOW64\odbcad32.exe. More details here > msdn.microsoft.com/.../ca6axakh(v=vs.80).aspx
Please explain Step 3 in more detail.