Index: trunk/BNC/src/bnchelp.html
===================================================================
--- trunk/BNC/src/bnchelp.html	(revision 9952)
+++ trunk/BNC/src/bnchelp.html	(revision 9953)
@@ -687,5 +687,5 @@
 Microsoft Installer (MSI) file. MSI files are used for installation, storage, and removal of programs.
 The BNC files are contained in a MSI package, which is used with the program's client-side installer service,
-an .EXE file, to open and install the program. We used the MinGW Version 4.4.0 compiler to create BNC for Windows.
+an .EXE file, to open and install the program. We used the MSVC 2019 compiler to create BNC for Windows.
 After installation your 'bnc.exe' file shows up e.g. under 'All Programs'.
 </p>
@@ -722,52 +722,54 @@
 
 <p><b>MS Windows Systems, Shared Library</b><br>
-This explains how to install a shared Qt 4.8.5 library on MS Windows systems to then create your own shared build of BNC.
-</p>
-
-<ol type="1">
-<li>Supposing that 'Secure Socket Layer (SSL)' is not available on you system, you should install OpenSSL libraries
-in C:\OpenSSL-Win32. They are available e.g. from <a href="http://igs.bkg.bund.de/root_ftp/NTRIP/software/Win32OpenSSL-1_0_1e.exe"
-target="_blank">http://igs.bkg.bund.de/root_ftp/NTRIP/software/Win32OpenSSL-1_0_1e.exe</a>.
-See <a href="http://slproweb.com/products/Win32OpenSSL.html" target="_blank">http://slproweb.com/products/Win32OpenSSL.html</a>
-for other SSL resources. Ignore possibly occurring comments about missing components during installation.</li>
-
-<li>Download MinGW compiler Version 4.4.0 e.g. from <a href="http://igs.bkg.bund.de/root_ftp/NTRIP/software/MinGW-gcc440_1.zip" target="_blank">http://igs.bkg.bund.de/root_ftp/NTRIP/software/MinGW-gcc440_1.zip</a></li>
-
-<li>Unzip the ZIP archive and move its contents to a directory <i>C:\MinGW</i>. Now you can do either (4) or (5, 6, 8, 9, 10). Following (4) is suggested.</li>
-
-<li>Download file 'qt-win-opensource-4.8.5-mingw.exe' (317 MB) e.g. from <a href="https://download.qt.io/archive/qt/4.8/4.8.5/"
-   target="_blank">https://download.qt.io/archive/qt/4.8/4.8.5/</a>. Execute this file to install a pre-compiled shared Qt library.</li>
-
-<li>Download file 'qt-everywhere-opensource-src-4.8.5.zip' (269 MB) e.g. from
-   <a href="https://download.qt.io/archive/qt/4.8/4.8.5/" target="_blank">https://download.qt.io/archive/qt/4.8/4.8.5/</a></li>
-
-<li>Unzip the ZIP archive and move the contents of the contained directory into a directory <i>C:\Qt\4.8.5</i>.</li>
+This section contains some hints how to build a shared Qt 15.5.8 library on MS Windows systems to then create your own shared build of BNC.
+But is is highly recommended to use the dynamically compiled shared library build for Mircrosoft Windows systems which is provided as
+Microsoft Installer (MSI) file.
+</p>
+<ul>
+<li>Support for Secure Sockets Layer (SSL) communication is provided by the OpenSSL Toolkit, which must be obtained separately.
+Download the latest version of the toolkit that is supported by Qt and install OpenSSL libraries in C:\OpenSSL-Win64.
+The OpenSSL libraries are looked up first in the drectory of the executable, then in the Windows System directory,
+and finally in all directories listed in the PATH environment variable.
+You can configure how Qt uses OpenSSL by setting either the -openssl / -openssl-runtime or -openssl-linked configure flags.
+To link Qt Network against OpenSSL libraries, set the -openssl-linked configure argument and use the OPENSSL_PREFIX variable
+to let Qt correctly locate and build against your OpenSSL installation.
+For example: configure -openssl-linked OPENSSL_PREFIX="C:\OpenSSL-Win64".</li>
+<li>The following tools are required at build time:
+<ul>
+    <li>Python 2.7.5 or later. Python 3 is not supported.</li>
+    <li> Windows binaries of Bison, Flex, GPerf from the GnuWin32 project (<a href="http://gnuwin32.sourceforge.net/" target="_blank">http://gnuwin32.sourceforge.net/</a>), required to build QtWebEngine</li>
+    <li>Node.js version 12 or later</li>
+    <li>Visual Studio 2019 or clang-cl (msvc mode) version 8 or later, required to build QtWebEngine</li>
+    <li>Jom is recommended because it is a clone of nmake to support the execution of multiple independent commands in parallel.
+        It basically adds the -j command line switch similar to GNU make</li>
+    <li>Active Template Library (ATL), usually included in the Visual Studio installation</li>
+    <li>Windows 10 SDK version 10.0.19041 or later</li>
+</ul>
+and its location should be listed in the PATH environment variable.
+</li>
+<li>To use OpenGL, pass the command line option '-opengl desktop' to the configure script.</li>
+<li>Download the file 'qt-everywhere-opensource-src-5.15.8.zip' e.g. from
+<a href="https://download.qt.io/official_releases/qt/5.15/5.15.8/single/"
+target="_blank">https://download.qt.io/official_releases/qt/5.15/5.15.8/single/</a>
+and unzip the ZIP archive and move the contents of the contained directory into a directory e.g. C:\Qt\qt-everywhere-src-5.15.8. </li>
+<li>Open a x64 Native Tools Command Promt for VS 2019 </li>
+<li>Go to directory C:\Qt\5.15.8 and configure Qt using command
+<pre>
+.\configure -prefix C:\Qt\5.15.8\ -opensource -release -nomake tests -nomake examples -skip qtdoc -platform win32-msvc -mp -confirm-license -openssl-linked OPENSSL_PREFIX="C:\OpenSSL-Win64" -opengl desktop -webengine-proprietary-codecs -recheck-all
+</pre>
+</li>
+<li>Compile Qt using command <pre>  jom or nmake </pre></li>
+<li>Install Qt using command <pre>  jom install or nmake install</pre></li>
 
 <li>Create somewhere a file QtEnv.bat with the following content:
 <pre>
-   set QTDIR=C:\Qt\4.8.5
-   set PATH=%PATH%;C:\MinGW\bin;C:\Qt\4.8.5\bin
-   set QMAKESPEC=C:\Qt\4.8.5\mkspecs\win32-g++
-</pre></li>
-
-<li>Open a command line window and execute file QtEnv.bat</li>
-
-<li>Go to directory C:\Qt\4.8.5 and configure Qt using command
-<pre>
-   configure -fast -webkit -release -nomake examples -nomake tutorial
-             -openssl -I C:\OpenSSL-Win32\include
-</pre></li>
-
-<li>Compile Qt using command
-<pre>
-   mingw32-make
+   set QTDIR=C:\Qt\5.15.8
+   set PATH=%PATH%C:\Qt\5.15.8\bin;
+   set QMAKESPEC=C:\Qt\5.15.8\mkspecs\win32-msvc
 </pre>
-This may take quite a long time. Don't worry if the compilation process runs into a problem after some time. It is likely that the libraries you require are already generated at that time.<br>
-Should you want to reconfiguring Qt following steps (8)-(10) you first need to clean the previous configuration using command 'mingw32-make confclean'. Run command 'mingw32-make clean' to delete previously compiled source code.</li>
+and excute file QtEnv.bat</li>
 
 <li>Download latest BNC from SVN repository <a href="http://software.rtcm-ntrip.org/svn/trunk/BNC"
 target="_blank">http://software.rtcm-ntrip.org/svn/trunk/BNC</a>.</li>
-
-<li>Open command line window and execute file QtEnv.bat, see (7)</li>
 
 <li>Go to directory BNC and enter command
@@ -778,15 +780,8 @@
 <li>Enter command
 <pre>
-   mingw32-make
+   jom (or nmake)
 </pre></li>
-
 <li>Find binary file bnc.exe in directory named src.</li>
-
-<li>Extend the Windows environment variable PATH by C:\Qt\4.8.5\bin.</li>
-</ol>
-<p>
-Steps (11)-(15) can be repeated whenever a BNC update becomes available. Running bnc.exe on a windows system
-requires (1) when using the NTRIP Version 2s option for stream transfer over TLS/SSL.
-</p>
+</ul>
 <p>
 <b>Linux Systems</b><br>
@@ -804,45 +799,5 @@
 <b>Mac OS X Systems</b><br>
 </p>
-
-<u>Xcode and Qt Installation</u><br>
-<p>
-Xcode and Qt are required to compile BNC on OS X. Both tools are freely available. Xcode can be downloaded from the
-App Store or the Apple Developer Connection website. Once installed, run Xcode, go to 'Preferences->Downloads' and install the Command Line Tools component. Qt can be downloaded from the Qt Project website. We suggest installing version 4.8.4 or higher. The Qt libraries for Mac can be downloaded from <u>http://www.qt.io/download</u>. Once downloaded, mount the disk image, run the Qt.mpkg package and follow instructions from the installation wizard.
-</p>
-
-<u>Compiling BNC</u><br>
-<p>
-The version of qmake supplied in the Qt binary package is configured to use the macx-xcode specification.
-This can be overridden with the '-spec macx-g++' option which makes it possible to use qmake to create a Makefile to
- be used by 'make'.
-</p>
-<p>
-From the directory where bnc.pro is located, run 'qmake' to create the Makefile and then 'make' to compile the binary.
-<pre>
-   qmake -spec macx-g++ bnc.pro
-   make
-</pre>
-Refer to the following webpage for further information: <a href="http://doc.qt.io/qt-4.8/qmake-platform-notes.html" target="_blank">http://doc.qt.io/qt-4.8/qmake-platform-notes.html</a>.
-</p>
-
-<p>
-<u>Bundle Deployment</u><br>
-</p>
-<p>
-When distributing BNC it is necessary to bundle in all related Qt resources in the package. The Mac Deployment Tool
-has been designed to automate the process of creating a deployable application bundle that contains the Qt libraries
-as private frameworks. To use it, issue the following commands where bnc.app is located.
-</p>
-
-<pre>
-   macdeployqt bnc.app -dmg
-</pre>
-<p>
-Refer to the following webpage for further information: <a href="http://doc.qt.io/qt-4.8/deployment-mac.html"
-target="_blank">http://doc.qt.io/qt-4.8/deployment-mac.html</a>.
-</p>
-<p>
-Once a DMG file for BNC is created, you can double click it and install BNC by dragging the 'bnc.app' icon to your
-'Applications' folder. To start BNC, double click on '/Aplications/bnc.app'.
+Please use the precompiled build of BNC
 </p>