I want to save file as:

firstname.lastname.docx
in folder c:\users\savvy\documents\final doc\
firstname and lastname are bookmarks from userform

but am getting

runtime error 5152
this is not a valid filename

code:
strPath = Environ("USERPROFILE") & "\Documents\final doc"
ActiveDocument.SaveAs strPath & TextBox2.Text & "." & TextBox1.Text & ".docx"

any advice appreciated