Using parameters like this in a query is not a good practice.
A better approach is to provide a form where the user can select the company name from a list (List box or Combo box) of Valid Choices and then use that as the criteria for opening a report. For example
If Not IsNull(Me.lstCompany) Then
DoCmd.OpenReport "rptCompany", acViewPreview, , "Company_ID = " & Me.lstCompany
Else
' If no company is selected then you don't send a criteria to the report
DoCmd.OpenReport "rptCompany", acViewPreview
End If
and you will notices that in this example I've used the Primary Key of the Company table for the filter. The list box uses this field as its first column, actually column(0), with its column width set to zero and the Company Name as the second column that the user does see.
Giving users direct access to a table or query is not good practice. Users should be presented with data in either a form or report where there is some control (eg Validation) on what the user can add, edit or delete.