https://www.infopathdev.com:443/forums/41.aspxIf you're not sure where to ask your question, ask it here. If necessary, our moderators will make sure it gets classified in the correct board.enCommunityServer 2007 SP3 (Build: 31118.962)https://www.infopathdev.com:443/forums/thread/105484.aspxThu, 11 Feb 2016 22:23:46 GMT033a2e2d-04e2-4a9d-be01-a4634161eefd:105484nallsm10https://www.infopathdev.com:443/forums/thread/105484.aspxhttps://www.infopathdev.com:443/forums/commentrss.aspx?SectionID=41&PostID=105484<p>InfoPath 2010<br />I have a form called On Duty where you&nbsp;select a person from a list and enter in their&nbsp;&quot;start date&quot; and &quot;stop date&quot;.&nbsp;&nbsp;The same person may have multiple entries with different date ranges.&nbsp; I want to create a validation so&nbsp;to avoid overlapping dates.&nbsp; Here&#39;s an example;</p><p>1st entry:</p><ul><li>Name: Michael</li><li>Start Date: 1.15/16</li><li>Stop Date: 1/31/16</li></ul><p>2nd entry: </p><ul><li>Name: Michael</li><li>Start Date: 2/5/16</li><li>Stop Date: 2/10/16&nbsp;</li></ul><p>3rd entry:</p><ul><li>Name: Steve</li><li>Start Date: 1/25/16</li><li>Stop Date: 2/18/16</li></ul><p>4th&nbsp;entry:</p><ul><li>Name: Michael</li><li>Start Date: 2/9/16 (I want this date to give an error because this date falls between the dates entered on Michael&#39;s prior entry)</li><li>Stop Date: 2/21/16</li></ul><p>How do I create this validation?<br />Michael&nbsp;</p>