Variable Workbook Name

I'm fairly new to the Macro stuff so forgive me if this is an elementary problem. I couldn't seem to find any solutions with a search.

Background:

I have a workbook with a macro that is pulling information from a different closed workbook.

I am trying to open this workbook whose name changes occasionally. Inside the workbook with the macro, I have the user make sure a cell has the correct workbook name that they are trying to consolidate information from. I then use this cell as the variable.

Book = DiagramWs.Range(BW2).Value

Workbooks.Open ("M:\Test\Test DB\ & Book & .xls")

I get the error Method 'range of worksheet failed' highlighted on the Workbooks.Open code line.

Thanks for any help or suggestions!

Laura

Thanks I figured it was some type of syntax!

Thanks,
Laura