invalid object name 'sys.objects'

Our scripts have a sql server 2005 requirement.Some of our customers have reported the error invalid object name 'sys.objects' . On going through some of the posts in this forum it seems to me that sys.objects is a view introduced in sql server 2005. So i suspect this problem might be occuring because the user is trying to run our script on an older version of sql server. I want to know if this is the only possibility or if there is any other case this error can occur in sql server 2005.

Thanks,
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