idspnInfoPath_NV) is set to be the e-mail editor. However, InfoPath is unavailable, not installed, or a different version ...

(!idspnInfoPath_NV) is set to be the e-mail editor. However, InfoPath is unavailable, not installed, or a different version from Outlook. The InfoPath Filler will be turned off, and the Outlook e-mail editor will be used instead. Try to repair the InfoPath installation, and then turn on InfoPath as the e-mail editor again.