When helping users with problems we have found it dangerous to make assumptions about the version of InfoPath that is installed.

The user must first identify the version build number of his/her InfoPath:

1. Click Start, and then click Control Panel.

2. In Control Panel, click Add or Remove Programs.

3. In Add or Remove Programs, locate and then click the appropriate Office edition or individual product.

4. Click the resulting Click here for support information link. A message box displays the correct version information for the product as it is recorded by the Microsoft Windows Installer.

Here are the Version Builds by year released: 

InfoPath 2003 - 11.0.5531.5606
InfoPath 2003 SP1 - 11.0.6357.6360
InfoPath 2003 SP2 - 11.6565.6568
InfoPath 2003 SP3 - 11.0.8173.0

InfoPath 2007 - 12.0.6028.5000
InfoPath 2007 SP1 - 12.0.6214.1000
InfoPath 2007 SP2 - 12.0.6425.1000

InfoPath 2010 - 14.0.4006.1010