Run time error 2202

Hi all.

I get the following error when printing a report (it was working fine for the past 3 months until today), the report prints images with each record.

Run-time error '2220':
Microsoft Office Access can't open the file '\\path\909655.bmp'

This is the code I use to populate the image:
Option Compare Database
Option Explicit

Private Sub Detail_Format(Cancel As Integer, FormatCount As Integer)

If Me!Expr3 = "" Or IsNull(Me!Expr3) Then

Me!ImageFrame.Visible = 0
Else
    Me!ImageFrame.Visible = -1
    Me!ImageFrame.Picture = Me!Expr3
End If

End Sub

The Debugger highlights the following line: Me!ImageFrame.Picture = Me!Expr3


Expr3 is the following: Expr3: IIf([ImageFile] Is Null Or [ImageFile]="","","\\win2k3-2\apps\MAS90\images\ASC\" & [ImageFile])

Any ideas?