Index: Ringtoets/Integration/test/Ringtoets.Integration.Forms.Test/WmtsConnectionInfoReaderTest.cs
===================================================================
diff -u -r41837216a2f3d66c3084500f4dcef57c478bfef5 -r4f2d8bc47cb1935643c427e0d3bd69a06bddaa7c
--- Ringtoets/Integration/test/Ringtoets.Integration.Forms.Test/WmtsConnectionInfoReaderTest.cs	(.../WmtsConnectionInfoReaderTest.cs)	(revision 41837216a2f3d66c3084500f4dcef57c478bfef5)
+++ Ringtoets/Integration/test/Ringtoets.Integration.Forms.Test/WmtsConnectionInfoReaderTest.cs	(.../WmtsConnectionInfoReaderTest.cs)	(revision 4f2d8bc47cb1935643c427e0d3bd69a06bddaa7c)
@@ -20,8 +20,10 @@
 // All rights reserved.
 
 using System;
-using System.Collections.Generic;
 using System.IO;
+using System.Linq;
+using System.Xml;
+using Core.Common.IO.Exceptions;
 using Core.Common.TestUtil;
 using NUnit.Framework;
 
@@ -86,17 +88,33 @@
         }
 
         [Test]
+        public void ReadWmtsConnectionInfos_FileMissing_ThrowsCriticalFileReadException()
+        {
+            // Setup
+            string filePath = Path.Combine(testPath, Path.GetRandomFileName());
+            var reader = new WmtsConnectionInfoReader();
+
+            // Call
+            TestDelegate call = () => reader.ReadWmtsConnectionInfos(filePath);
+
+            // Assert
+            var expectedMessage = $"Fout bij het lezen van bestand '{filePath}': het bestand bestaat niet.";
+            string actualMessage = Assert.Throws<CriticalFileReadException>(call).Message;
+            Assert.AreEqual(expectedMessage, actualMessage);
+        }
+
+        [Test]
         public void ReadWmtsConnectionInfos_FileWithTwoWmtsConnectionInfos_ReturnsExpectedWmtsConnectionInfos()
         {
             // Setup
             string filePath = Path.Combine(testPath, "twoValidWmtsConnectionInfos.txt");
             var reader = new WmtsConnectionInfoReader();
 
             // Call
-            List<WmtsConnectionInfo> readConnectionInfos = reader.ReadWmtsConnectionInfos(filePath);
+            WmtsConnectionInfo[] readConnectionInfos = reader.ReadWmtsConnectionInfos(filePath).ToArray();
 
             // Assert
-            Assert.AreEqual(2, readConnectionInfos.Count);
+            Assert.AreEqual(2, readConnectionInfos.Length);
             var firstExpected = new WmtsConnectionInfo(@"Actueel Hoogtebestand Nederland (AHN1)", @"https://geodata.nationaalgeoregister.nl/tiles/service/wmts/ahn1?request=GetCapabilities");
             var secondExpected = new WmtsConnectionInfo(@"Zeegraskartering", @"https://geodata.nationaalgeoregister.nl/zeegraskartering/wfs?request=GetCapabilities");
 
@@ -112,17 +130,133 @@
             var reader = new WmtsConnectionInfoReader();
 
             // Call
-            List<WmtsConnectionInfo> readConnectionInfos = reader.ReadWmtsConnectionInfos(filePath);
+            WmtsConnectionInfo[] readConnectionInfos = reader.ReadWmtsConnectionInfos(filePath).ToArray();
 
             // Assert
-            Assert.AreEqual(2, readConnectionInfos.Count);
+            Assert.AreEqual(2, readConnectionInfos.Length);
             var firstExpected = new WmtsConnectionInfo(@"Actueel Hoogtebestand Nederland (AHN1)", @"https://geodata.nationaalgeoregister.nl/tiles/service/wmts/ahn1?request=GetCapabilities");
             var secondExpected = new WmtsConnectionInfo(@"Zeegraskartering", @"https://geodata.nationaalgeoregister.nl/zeegraskartering/wfs?request=GetCapabilities");
 
             AssertAreEqual(firstExpected, readConnectionInfos[0]);
             AssertAreEqual(secondExpected, readConnectionInfos[1]);
         }
 
+        [Test]
+        public void ReadWmtsConnectionInfos_FileWithoutWmtsConnectionInfos_ReturnsEmptyList()
+        {
+            // Setup
+            string filePath = Path.Combine(testPath, "WmtsConnectionInfosZeroWmtsConnections.txt");
+            var reader = new WmtsConnectionInfoReader();
+
+            // Call
+            WmtsConnectionInfo[] readConnectionInfos = reader.ReadWmtsConnectionInfos(filePath).ToArray();
+
+            // Assert
+            Assert.AreEqual(0, readConnectionInfos.Length);
+        }
+
+        [Test]
+        public void ReadWmtsConnectionInfos_FileWithoutWmtsConnectionsElement_ThrowsCriticalFileReadException()
+        {
+            // Setup
+            string filePath = Path.Combine(testPath, "WmtsConnectionInfosWithoutWmtsConnectionsElement.txt");
+            var reader = new WmtsConnectionInfoReader();
+
+            // Call
+            TestDelegate call = () => reader.ReadWmtsConnectionInfos(filePath);
+
+            // Assert
+            var exception = Assert.Throws<CriticalFileReadException>(call);
+            string expectedMessage = $"Fout bij het lezen van bestand '{filePath}': het bestand "
+                                     + "kon niet worden geopend. Mogelijk is het bestand corrupt "
+                                     + "of in gebruik door een andere applicatie.";
+            Assert.AreEqual(expectedMessage, exception.Message);
+            Assert.IsInstanceOf<XmlException>(exception.InnerException);
+        }
+
+        [Test]
+        public void ReadWmtsConnectionInfos_FileEmptyUrlElement_WarnsAndReadsRestOfFile()
+        {
+            // Setup
+            string filePath = Path.Combine(testPath, "twoWmtsConnectionInfosOneEmptyUrl.txt");
+            var reader = new WmtsConnectionInfoReader();
+
+            WmtsConnectionInfo[] readConnectionInfos = null;
+
+            // Call
+            Action action = () => { readConnectionInfos = reader.ReadWmtsConnectionInfos(filePath).ToArray(); };
+
+            // Assert
+            string expectedMessage = $"Fout bij het lezen van bestand '{filePath}' waarbij Naam='First name' "
+                                     + "en URL='': het is niet mogelijk om een WMTS connectie aan te maken.";
+            TestHelper.AssertLogMessageWithLevelIsGenerated(action, Tuple.Create(expectedMessage, LogLevelConstant.Warn));
+
+            Assert.IsNotNull(readConnectionInfos);
+            Assert.AreEqual(1, readConnectionInfos.Length);
+            var expectedWmtsConnectionInfo = new WmtsConnectionInfo(@"second name",
+                                                                    @"https://domain.com");
+
+            AssertAreEqual(expectedWmtsConnectionInfo, readConnectionInfos[0]);
+        }
+
+        [Test]
+        public void ReadWmtsConnectionInfos_FileMissingOneUrlElement_SkipdAndReadsRestOfFile()
+        {
+            // Setup
+            string filePath = Path.Combine(testPath, "twoWmtsConnectionInfosOneWithoutUrlElement.txt");
+            var reader = new WmtsConnectionInfoReader();
+
+            // Call
+            WmtsConnectionInfo[] readConnectionInfos = reader.ReadWmtsConnectionInfos(filePath).ToArray();
+
+            // Assert
+            Assert.AreEqual(1, readConnectionInfos.Length);
+            var expectedWmtsConnectionInfo = new WmtsConnectionInfo(@"second name", @"https://domain.com");
+
+            AssertAreEqual(expectedWmtsConnectionInfo, readConnectionInfos[0]);
+        }
+
+        [Test]
+        public void ReadWmtsConnectionInfos_FileMissingOneNameElement_SkipdAndReadsRestOfFile()
+        {
+            // Setup
+            string filePath = Path.Combine(testPath, "twoWmtsConnectionInfosOneWithoutNameElement.txt");
+            var reader = new WmtsConnectionInfoReader();
+
+            // Call
+            WmtsConnectionInfo[] readConnectionInfos = reader.ReadWmtsConnectionInfos(filePath).ToArray();
+
+            // Assert
+            Assert.AreEqual(1, readConnectionInfos.Length);
+            var expectedWmtsConnectionInfo = new WmtsConnectionInfo(@"second name", @"https://domain.com");
+
+            AssertAreEqual(expectedWmtsConnectionInfo, readConnectionInfos[0]);
+        }
+
+        [Test]
+        public void ReadWmtsConnectionInfos_FileLocked_ThrowsCriticalFileReadException()
+        {
+            // Setup
+            string filePath = Path.Combine(testPath, Path.GetRandomFileName());
+            var reader = new WmtsConnectionInfoReader();
+
+            using (var fileDisposeHelper = new FileDisposeHelper(filePath))
+            {
+                fileDisposeHelper.LockFiles();
+
+                // Call
+                TestDelegate call = () => reader.ReadWmtsConnectionInfos(filePath);
+
+                // Assert
+                var exception = Assert.Throws<CriticalFileReadException>(call);
+                string expectedMessage = $"Fout bij het lezen van bestand '{filePath}': het bestand "
+                                         + "kon niet worden geopend. Mogelijk is het bestand corrupt "
+                                         + "of in gebruik door een andere applicatie.";
+                Assert.AreEqual(expectedMessage, exception.Message);
+                Assert.IsInstanceOf<IOException>(exception.InnerException);
+            }
+        }
+
         private static void AssertAreEqual(WmtsConnectionInfo expected, WmtsConnectionInfo actual)
         {
             Assert.AreEqual(expected.Name, actual.Name);