Running DataFlex Windows applications
To run DataFlex Windows applications, you need to purchase DataFlex Windows Client Licenses. A Client License allows you to run DataFlex applications for a set number of concurrent users.
On this page, you will find all versions of DataFlex Windows Client Licenses, including older ones. If you need older versions than the one listed here, please contact us.
Supported versions
Supported operating systems
For support go to
Changes between different DataFlex versions
Download prior DataFlex Windows Client versions
The client installer installs the DataFlex runtime which is required to run DataFlex windows programs. To develop DataFlex applications use the Studio installer, to deploy DataFlex web applications use the WebApp Server installer. The client installer uses a command line interface that describes what components to install, what installation path to use etc.
DataFlex 19.1.58 is an updated release that contains bug fixes for important issues reported by the development community. Most of these issues were new to DataFlex 19.1. The updates are available as complete new installations (including the Studio, Server and Client installations) and are meant to replace the previous release builds (DataFlex 19.1.56). For detailed information about the update see this document.
The client installer installs the DataFlex runtime which is required to run DataFlex windows programs. To develop DataFlex applications use the studio installer, to deploy DataFlex web applications use the WebApp Server installer. The client installer uses a command line interface that describes what components to install, what installation path to use etc.
The client installer uses a configuration file that describes what components to install, what installation path to use etc.
Recently, two issues were brought to our attention that we have addressed with in-line updates to DataFlex 18.x. Other than the information below, there are no changes to these releases.
As part of the Windows 10 Creators Update, Microsoft introduced an operating system bug that halts program execution when using the GetWindowLong function to retrieve information from a window that is not processing its message queue. This bug is not DataFlex specific, it was reported to Microsoft using test programs written in C.
Microsoft has acknowledged this bug and has stated their intention to address it in a future Windows 10 update. To respond to this issue in the shortest possible time for the benefit of our developers, we have created a work around in DataFlex for this operating system bug. We eliminated the use of the GetWindowLong call during initialization as it was a legacy technique to look for other DataFlex instances that is no longer used. This workaround is implemented in the DataFlex Virtual Machine (runtime) component (vdfvm18.dll).
DataFlex developer Raphael Theiler identified the potential for External XML Entity Injections (XXE) and exponential entity expansions to be exploited in DataFlex Web Services. We confirmed his findings and have addressed both vulnerabilities in an update to our Web Services engine.
During the same time period, we discovered that sending HTTP POST requests without a body to a JSON web service could cause a crash and have hardened Web Application Server against that scenario.
There are three changes in the update to the DataFlex Web Application Server Web Service Endpoint (waswsvc.dll) to address these issues.
The new components have been published for DataFlex 18.2 (original release date of July 2016).
As an alternative, a ZIP file (DataFlex18.2Update.zip) that contains the two changed components that can be applied to existing installations.
For DataFlex 2016/18.2, we recommend uninstalling version 18.2.68.9 and then installing the updated DataFlex 18.2.71.1. If you elect to update your environments with the DataFlex18.2Update.zip file, follow the instructions included in the ZIP.
The updated DataFlex 18.2.71.1 installations also contain the latest SQL Drivers (6.1.0.32) and related documentation. If you apply the virtual machine and web services updates manually with the DataFlex18.2Update.zip file, we recommend updating to the latest SQL drivers at the same time. You can obtain the SQL Driver update at: https://www.dataaccess.eu/resources/downloads/download-category/download-subcategory-842?dagapsg=80
The client installer uses a configuration file that describes what components to install, what installation path to use etc.
Recently, two issues were brought to our attention that we have addressed with in-line updates to DataFlex 18.x. Other than the information below, there are no changes to these releases.
As part of the Windows 10 Creators Update, Microsoft introduced an operating system bug that halts program execution when using the GetWindowLong function to retrieve information from a window that is not processing its message queue. This bug is not DataFlex specific, it was reported to Microsoft using test programs written in C.
Microsoft has acknowledged this bug and has stated their intention to address it in a future Windows 10 update. To respond to this issue in the shortest possible time for the benefit of our developers, we have created a work around in DataFlex for this operating system bug. We eliminated the use of the GetWindowLong call during initialization as it was a legacy technique to look for other DataFlex instances that is no longer used. This workaround is implemented in the DataFlex Virtual Machine (runtime) component (vdfvm18.dll).
DataFlex developer Raphael Theiler identified the potential for External XML Entity Injections (XXE) and exponential entity expansions to be exploited in DataFlex Web Services. We confirmed his findings and have addressed both vulnerabilities in an update to our Web Services engine.
During the same time period, we discovered that sending HTTP POST requests without a body to a JSON web service could cause a crash and have hardened Web Application Server against that scenario.
There are three changes in the update to the DataFlex Web Application Server Web Service Endpoint (waswsvc.dll) to address these issues.
The new components have been published for DataFlex 18.1 (original release date of July 2015) as ZIP file. The ZIP file (DataFlex18.1Update.Zip) contains the two changed components that can be applied to existing installations.
We recommend updating to the latest SQL drivers at the same time. You can obtain the SQL Driver update at: https://www.dataaccess.eu/resources/downloads/download-category/download-subcategory-842?dagapsg=80
The client installer uses a configuration file that describes what components to install, what installation path to use etc.
Recently, two issues were brought to our attention that we have addressed with in-line updates to DataFlex 18.x. Other than the information below, there are no changes to these releases.
As part of the Windows 10 Creators Update, Microsoft introduced an operating system bug that halts program execution when using the GetWindowLong function to retrieve information from a window that is not processing its message queue. This bug is not DataFlex specific, it was reported to Microsoft using test programs written in C.
Microsoft has acknowledged this bug and has stated their intention to address it in a future Windows 10 update. To respond to this issue in the shortest possible time for the benefit of our developers, we have created a work around in DataFlex for this operating system bug. We eliminated the use of the GetWindowLong call during initialization as it was a legacy technique to look for other DataFlex instances that is no longer used. This workaround is implemented in the DataFlex Virtual Machine (runtime) component (vdfvm18.dll).
DataFlex developer Raphael Theiler identified the potential for External XML Entity Injections (XXE) and exponential entity expansions to be exploited in DataFlex Web Services. We confirmed his findings and have addressed both vulnerabilities in an update to our Web Services engine.
During the same time period, we discovered that sending HTTP POST requests without a body to a JSON web service could cause a crash and have hardened Web Application Server against that scenario.
There are three changes in the update to the DataFlex Web Application Server Web Service Endpoint (waswsvc.dll) to address these issues.
The new components have been published for DataFlex 18.1 (original release date of July 2015) as ZIP file. The ZIP file (DataFlex18.1Update.Zip) contains the two changed components that can be applied to existing installations.
We recommend updating to the latest SQL drivers at the same time. You can obtain the SQL Driver update at: https://www.dataaccess.eu/resources/downloads/download-category/download-subcategory-842?dagapsg=80
The client installer uses a configuration file that describes what components to install, what installation path to use etc.
Download pre-releases of DataFlex Windows Client
The DataFlex Windows Client has everything you need to deploy Windows desktop applications on supported Microsoft operating systems.
The Client installation includes...
The Client Engine is designed to be locally installed on a specific machine for stand-alone application or in an network-accessible location for multi-user applications.
The Client installation program has configurable command line arguments that define various options, placement of files and the details displayed during installation.
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