Problem opening drawings in AutoCAD 2008

We have an issue with opening drawings received (as email attachments) from one of our consultants. We have two workstations, of similar spec
and identical OS, both running identical (I think) versions of AutoCAD 2008. The drawings (also created in AutoCAD 2008 and saved as AC1021/ AutoCAD2007) open fine on Workstation A, but Workstation B throws a "Drawing file is not valid" error.
An audit of the drawings on Workstation A shows no errors and, once resaved, they then open fine on Workstation B.
Any ideas what's going on?
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You might find it useful to download the free software for converting drawing formats, from:
http://www.dwggateway.com/pages/support/index.html
Just in case you have received a file that's not in your format.
Brian.
In article
snipped-for-privacy@gmail.com (strawberry) wrote:

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