diff --git a/OpenRA.Game/FileFormats/Png.cs b/OpenRA.Game/FileFormats/Png.cs
index d35e013e28..5f980ae33a 100644
--- a/OpenRA.Game/FileFormats/Png.cs
+++ b/OpenRA.Game/FileFormats/Png.cs
@@ -15,7 +15,7 @@ using System.IO;
 using System.Linq;
 using System.Net;
 using System.Text;
-using ICSharpCode.SharpZipLib.Checksums;
+using ICSharpCode.SharpZipLib.Checksum;
 using ICSharpCode.SharpZipLib.Zip.Compression.Streams;
 using OpenRA.Primitives;
 
diff --git a/OpenRA.Game/FileSystem/ZipFile.cs b/OpenRA.Game/FileSystem/ZipFile.cs
index a34e8c8a3e..e21214e833 100644
--- a/OpenRA.Game/FileSystem/ZipFile.cs
+++ b/OpenRA.Game/FileSystem/ZipFile.cs
@@ -33,7 +33,7 @@ namespace OpenRA.FileSystem
 			public ReadOnlyZipFile(Stream s, string filename)
 			{
 				Name = filename;
-				pkg = ZipFileHelper.Create(s);
+				pkg = new ZipFile(s);
 			}
 
 			public Stream GetStream(string filename)
@@ -113,7 +113,7 @@ namespace OpenRA.FileSystem
 				}
 
 				pkgStream.Position = 0;
-				pkg = ZipFileHelper.Create(pkgStream);
+				pkg = new ZipFile(pkgStream);
 				Name = filename;
 			}
 
diff --git a/OpenRA.Game/OpenRA.Game.csproj b/OpenRA.Game/OpenRA.Game.csproj
index 1dfc7e5bd4..ebe19e6bd2 100644
--- a/OpenRA.Game/OpenRA.Game.csproj
+++ b/OpenRA.Game/OpenRA.Game.csproj
@@ -160,7 +160,6 @@
     <Compile Include="Primitives\Size.cs" />
     <Compile Include="Primitives\SpatiallyPartitioned.cs" />
     <Compile Include="Primitives\ConcurrentCache.cs" />
-    <Compile Include="Primitives\ZipFileHelper.cs" />
     <Compile Include="SelectableExts.cs" />
     <Compile Include="Selection.cs" />
     <Compile Include="Server\Connection.cs" />
diff --git a/OpenRA.Game/Primitives/ZipFileHelper.cs b/OpenRA.Game/Primitives/ZipFileHelper.cs
deleted file mode 100644
index 925da06d97..0000000000
--- a/OpenRA.Game/Primitives/ZipFileHelper.cs
+++ /dev/null
@@ -1,46 +0,0 @@
-#region Copyright & License Information
-/*
- * Copyright 2007-2019 The OpenRA Developers (see AUTHORS)
- * This file is part of OpenRA, which is free software. It is made
- * available to you under the terms of the GNU General Public License
- * as published by the Free Software Foundation, either version 3 of
- * the License, or (at your option) any later version. For more
- * information, see COPYING.
- */
-#endregion
-
-using System.IO;
-using System.Text;
-using ICSharpCode.SharpZipLib.Zip;
-
-namespace OpenRA.Primitives
-{
-	public static class ZipFileHelper
-	{
-		/// <summary>
-		/// Creates a <see cref="ZipFile"/> with UTF8 encoding. Avoid using <see cref="ZipFile(Stream)"/> as you
-		/// cannot be sure of the encoding that will be used.
-		/// </summary>
-		public static ZipFile Create(Stream stream)
-		{
-			// SharpZipLib uses this global as the encoding to use for all ZipFiles.
-			// The initial value is the system code page, which causes several problems.
-			// 1) On some systems, the code page for a certain encoding might not even be installed.
-			// 2) The code page is different on every system, resulting in unpredictability.
-			// 3) The code page might not work for decoding some archives.
-			// We set the default to UTF8 instead which fixes all these problems.
-			ZipConstants.DefaultCodePage = Encoding.UTF8.CodePage;
-			return new ZipFile(stream);
-		}
-
-		/// <summary>
-		/// Creates a <see cref="ZipFile"/> with UTF8 encoding. Avoid using <see cref="ZipFile(FileStream)"/> as you
-		/// cannot be sure of the encoding that will be used.
-		/// </summary>
-		public static ZipFile Create(FileStream stream)
-		{
-			ZipConstants.DefaultCodePage = Encoding.UTF8.CodePage;
-			return new ZipFile(stream);
-		}
-	}
-}
diff --git a/OpenRA.Mods.Common/Widgets/Logic/Installation/DownloadPackageLogic.cs b/OpenRA.Mods.Common/Widgets/Logic/Installation/DownloadPackageLogic.cs
index 9c80099f83..6dea1a00a9 100644
--- a/OpenRA.Mods.Common/Widgets/Logic/Installation/DownloadPackageLogic.cs
+++ b/OpenRA.Mods.Common/Widgets/Logic/Installation/DownloadPackageLogic.cs
@@ -15,6 +15,7 @@ using System.ComponentModel;
 using System.IO;
 using System.Net;
 using System.Text;
+using ICSharpCode.SharpZipLib.Zip;
 using OpenRA.Primitives;
 using OpenRA.Support;
 using OpenRA.Widgets;
@@ -144,7 +145,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 				try
 				{
 					using (var stream = File.OpenRead(file))
-					using (var z = ZipFileHelper.Create(stream))
+					using (var z = new ZipFile(stream))
 					{
 						foreach (var kv in download.Extract)
 						{
diff --git a/thirdparty/fetch-thirdparty-deps.ps1 b/thirdparty/fetch-thirdparty-deps.ps1
index b00eec957b..fac79da9ea 100644
--- a/thirdparty/fetch-thirdparty-deps.ps1
+++ b/thirdparty/fetch-thirdparty-deps.ps1
@@ -30,8 +30,8 @@ if (!(Test-Path "StyleCop.dll"))
 if (!(Test-Path "ICSharpCode.SharpZipLib.dll"))
 {
 	echo "Fetching ICSharpCode.SharpZipLib from NuGet."
-	./nuget.exe install SharpZipLib -Version 0.86.0 -ExcludeVersion -Verbosity quiet -Source nuget.org
-	cp SharpZipLib/lib/20/ICSharpCode.SharpZipLib.dll .
+	./nuget.exe install SharpZipLib -Version 1.1.0 -ExcludeVersion -Verbosity quiet -Source nuget.org
+	cp SharpZipLib/lib/net45/ICSharpCode.SharpZipLib.dll .
 	rmdir SharpZipLib -Recurse
 }
 
diff --git a/thirdparty/fetch-thirdparty-deps.sh b/thirdparty/fetch-thirdparty-deps.sh
index d97214439d..4e93e03ac1 100755
--- a/thirdparty/fetch-thirdparty-deps.sh
+++ b/thirdparty/fetch-thirdparty-deps.sh
@@ -29,8 +29,8 @@ fi
 
 if [ ! -f ICSharpCode.SharpZipLib.dll ]; then
 	echo "Fetching ICSharpCode.SharpZipLib from NuGet"
-	../noget.sh SharpZipLib 0.86.0
-	cp ./SharpZipLib/lib/20/ICSharpCode.SharpZipLib.dll .
+	../noget.sh SharpZipLib 1.1.0
+	cp ./SharpZipLib/lib/net45/ICSharpCode.SharpZipLib.dll .
 	rm -rf SharpZipLib
 fi