diff --git a/net-core/Ical.Net/CalendarComponents/VTimeZone.cs b/net-core/Ical.Net/CalendarComponents/VTimeZone.cs
index b3883c3c7..14b91622b 100644
--- a/net-core/Ical.Net/CalendarComponents/VTimeZone.cs
+++ b/net-core/Ical.Net/CalendarComponents/VTimeZone.cs
@@ -44,7 +44,7 @@ public static VTimeZone FromDateTimeZone(string tzId, DateTime earlistDateTimeTo
             // Only include historical data if asked to do so.  Otherwise,
             // use only the most recent adjustment rules available.
             var intervals = vTimeZone._nodaZone.GetZoneIntervals(earliest, Instant.FromDateTimeOffset(DateTimeOffset.Now))
-                .Where(z => z.HasStart && z.Start != Instant.MinValue && z.HasEnd)
+                .Where(z => z.HasStart && z.Start != Instant.MinValue)
                 .ToList();
 
             var matchingDaylightIntervals = new List<ZoneInterval>();
@@ -75,7 +75,7 @@ public static VTimeZone FromDateTimeZone(string tzId, DateTime earlistDateTimeTo
                 vTimeZone.AddChild(latestStandardTimeZoneInfo);
 
                 // check to see if there is no active, future daylight savings (ie, America/Phoenix)
-                if (latestStandardInterval != null && latestStandardInterval.End != Instant.MaxValue)
+                if (latestStandardInterval != null && (latestStandardInterval.HasEnd ? latestStandardInterval.End : Instant.MaxValue) != Instant.MaxValue)
                 {
                     //daylight
                     var daylightIntervals = intervals.Where(x => x.Savings.ToTimeSpan() != new TimeSpan(0)).ToList();
@@ -130,7 +130,7 @@ private static VTimeZoneInfo CreateTimeZoneInfo(List<ZoneInterval> matchedInterv
                 throw new InvalidOperationException("oldestInterval was not found");
             }
 
-            var previousInterval = intervals.SingleOrDefault(x => x.End == oldestInterval.Start);
+            var previousInterval = intervals.SingleOrDefault(x => (x.HasEnd ? x.End : Instant.MaxValue) == oldestInterval.Start);
 
             var delta = new TimeSpan(1, 0, 0);