If you already have Microsoft Access 2003 or earlier installed on your computer, you do not need to install the Microsoft Access Report Viewer. Access already includes the option to save a report in the proper format for those with the Report Viewer to be able to open and view an Access report. However, if you are using Access 2007, you should install the Microsoft Access Report Viewer - formally named the Microsoft Access Snapshot Viewer.
Access 2007 provides the ability to email a snapshot directly from Access, but if you want to export a snapshot any other way, you must have the Report Viewer application installed. It should also be installed onto the computer of a user that does not have Access installed but needs to be able to view reports. The Microsoft Access Report Viewer can be installed on computers running any version of Windows from 95 forward.
To install the Report Viewer, go to the Microsoft Access Snapshot Viewer page on the Microsoft Download Center and click the Download button. Click the Save File button on the Opening snpvw.exe dialog box. Save the file where you can easily find it, such as on your Desktop. Once the download is complete, double click the snpvw.exe file and click Run to start the installation process.

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If you agree to the Licensing Agreement, click Yes. Click Continue when the Microsoft Access Report Viewer setup screen starts. Change the destination folder if desired, otherwise simply click OK, and then click the Complete Install button when prompted. Click OK when you receive a message that the Microsoft Access Report Viewer was successfully installed.

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