ThinLinc 4.9.0 Release Notes


Cendio are proud to present ThinLinc 4.9.0, with more than 80 enhancements and fixes. The most prominent changes are:

  • The Windows client is now available in a 64-bit version, allowing better performance on modern systems.
  • Shadowing notification is now more reliable and interactive, allowing end users more control of their sessions.
  • Windows 2016 is now supported both as a client platform and as a server for ThinLinc's Windows integration. Many improvements have also been made to the Windows integration.

ThinLinc works on most modern Linux distributions. We recommend that you deploy ThinLinc on one of these tested platforms:

  • Red Hat Enterprise Linux Server 7 (x86_64)
  • SUSE Linux Enterprise Server 12 (x86_64)
  • Ubuntu Desktop 16.04 (x86_64)

Please note that ThinLinc is supported on any platform that fulfills our documented requirements. This includes Oracle Linux, Linux Mint, and Debian.

Changes in This Release

In the list below, the bug number is given in parentheses. For more information, visit


  • A workaround has been added for a bug in the reference SELinux profile when used together with Firefox 52 ESR. The bug would cause crashes in Firefox and error messages in the system log files. (6976, 6993)

  • A user session could crash under some circumstances when used with KDE. This issue has been fixed. (7010)

  • GNOME Flashback now starts up correctly on Ubuntu 16.04. (7011)

  • New shadowing mechanism that brings the possibility to configure different shadowing modes. (37)

    You can now choose one of the following shadowing modes:

    • Reject all shadowing requests
    • Shadowing of a user without notification
    • Shadowing of a user with notification
    • Shadowing where the user are in control of accepting / rejecting a shadowing request

    The default behaviour of shadowing for an installation has changed from silent shadowing of a user (no notification), to were the user is interactively asked to accept or reject the shadowing request.

    This change of shadowing will also solve several issues with erratic shadowing notifications. (5737, 5810)

  • Upgrading a ThinLinc system with disconnected sessions could take an unreasonable amount of time if SELinux was enabled. This issue has been fixed. (7075)

  • ThinLinc Web Integration no longer supports trying to detect and install the native ThinLinc client. This feature required Java Applet support, so in practice very few systems supported it. (4521)

  • It is now possible to install ThinLinc on a system where /usr/local is not writable. (5941)

  • SELinux warnings will no longer be produced when creating new ThinLinc sessions on Fedora 27. (7150)

  • Added a workaround for a bug on Red Hat Enterprise Linux 7 that would prevent reconnections to sessions created before a Thinlinc Server upgrade. (7161)

  • If it takes a long time to scan the system fonts, then a progress dialog will be shown to the user until the scan has completed. This generally happens on the first login. (7159)


  • libtasn1 has been upgraded to version 4.12. (6212)
  • GnuTLS has been updated to version 3.5.12. (6211)
  • OpenSSL has been updated to version 1.0.2l. (6214)
  • OpenSSH has been updated to version 7.5p1. The ThinLinc Client no longer supports the 3des-cbc block cipher. (6213)
  • Freetype has been upgraded to version 2.8.0. This upgrade is a big jump and includes many bugfixes and a few non critical vulnerabilities. (5160)

Native Client

  • Windows clients are now available both for native 64-bit and 32-bit environments. The single universal installer will automatically detect which binaries to install. (3231)
  • Windows 2016 is now a supported platform for the ThinLinc client. (7054)
  • The ThinLinc Client on Windows will now connect significantly faster. (7082)
  • Fixed a bug where the client would not start if a line in a configuration file exceeded 1020 characters. (5834)
  • The ThinLinc Client on macOS will no longer have its user interface presented in high resolution on high DPI/Retina screens. This improvement was added in ThinLinc 4.8.0 but many systems experienced significant performance issues as a result of this. The interface is now restored to the older, low resolution mode. (7047)
  • The ThinLinc Client on Windows will no longer stop responding when connecting and the user has a large number of sessions running. (7089)
  • Identical SSH banners will no longer display twice during connection. (4533)
  • If it takes a long time to scan the system fonts, then a progress dialog will be shown to the user until the scan has completed. This generally happens on the first use of the ThinLinc client. (7159)

ThinLinc Web Access

  • Fixed a bug where clicking multiple times on the login button in ThinLinc Web Access could cause multiple sessions to be started for that user. (6223)
  • An issue in ThinLinc Web Access where the mouse button state could get out of sync has been fixed. (6224)

Printing Support

  • The PDF converter in the ThinLinc client has been upgraded in order to fix a security issue where a malicious server could possibly take control of the client. (7030)


  • The default permissions of the configuration file for ThinLinc Web Administration allowed users to view a hash of the configured password to access tlwebadm. This file is now readable by root only. (7043)

Windows Integration

  • Windows Server 2016 is now supported for use as a RDP server. (6096)
  • Windows session can now be resized interactively and dynamically, both when connecting to a full desktop and when connecting to a single applications. (7094)
  • Colored cursors are now supported when connecting to a Windows desktop or application. (5020)
  • Improved image quality where Remote Desktop Servers does not support 24-bit color. If supported, 32-bit color will be used instead of falling back to 16-bit color. (5753)
  • Fixed a bug for Windows connections where resizing the session window caused the background to disappear and parts of the session to appear black. (5290)
  • Fixed a bug where dead keys was not working as expected when using en-us-intl keymap and connecting to a Windows desktop or application. (7024)
  • Fixed a bug where the mouse cursor would disappear sometimes when connecting to a Windows desktop or application. (6173)
  • Fixed a bug where an automatic reconnect to the Windows server could result in the user being asked for credentials. (7094)
  • Fixed a bug where a "incorrect pin" message would sometimes be displayed when using Smart Card Authentication and connecting to a Windows desktop or application. (7144)

Configuration Changes


  • The configuration parameter '/vsmserver/allowed_shadowers' in vsmserver.hconf has been renamed to '/shadowing/allowed_shadowers' and moved to shadowing.hconf. (37)
  • New parameter: /shadowing/shadowing_mode. Controls which shadowing mode to use, default value is 'ask'. (37)


  • The default value for /vsmagent/display_min was changed from 1 to 10 due to collisions with local console display. (5643)
  • The default value for /utils/tl-mount-localdrives/mount_args no longer includes -n nor fg as they are no longer needed. (7087)

A complete configuration reference can be found in the ThinLinc Administrators Guide.

Corrected Issues

ThinLinc has also been enhanced in many other ways. The complete list of corrected issues is:

  37, 2822, 3231, 4306, 4478, 4521, 4533, 4914, 5020, 5068, 5089,
5160, 5244, 5247, 5290, 5643, 5737, 5744, 5753, 5810, 5834, 5886,
5887, 5941, 6096, 6161, 6173, 6188, 6195, 6211, 6212, 6213, 6214,
6223, 6224, 6347, 6963, 6968, 6971, 6976, 6983, 6986, 6990, 6992,
6993, 6994, 6995, 7010, 7011, 7016, 7024, 7025, 7027, 7030, 7032,
7033, 7035, 7043, 7045, 7047, 7050, 7052, 7053, 7054, 7056, 7057,
7060, 7068, 7070, 7074, 7075, 7081, 7082, 7085, 7089, 7094, 7095,
7096, 7130, 7138, 7144, 7150, 7159, 7161
Debian is a registered trademark of Software in the Public Interest, Inc.
Fedora is a registered trademark of Red Hat, Inc.
Firefox is a registered trademark of The Mozilla Foundation.
Java is a registered trademark of Oracle Corporation.
Linux is a registered trademark of Linus Torvalds.
Linux Mint is a trademark of Linux Mark Institute.
Oracle is a registered trademark of Oracle Corporation.
macOS is a registered trademark of Apple Computer, Inc.
PostScript is a registered trademark of Adobe Systems Inc.
Red Hat is a registered trademark of Red Hat, Inc.
SUSE is a registered trademark of SUSE LLC.
ThinLinc is a registered trademark of Cendio AB.
Ubuntu is a registered trademark of Canonical Ltd.
Windows is a registered trademark of Microsoft, Inc.

Frequently Asked Questions

  • ThinLinc is packaged in subscriptions with a tiered pricing system. A higher number of subscriptions will give a lower price. The subscriptions can be purchased for different periods, 12, 36 and 60 month. A longer duration will give a greater price. The payment of the subscriptions is done in advance.

    The default rule is that the prices are set in accordance with the number of subscriptions that are purchased at the actual call off. Deviation from this can be eventually agreed if a roll-out plan can be committed in advance.

  • Every valid ThinLinc Subscription Agreement has a specific ID. Contact Cendio at and refer to your ID, and we will issue new user licenses for you.

  • Contact Cendio support team at And refer to your ThinLinc Subscription ID in your support request.

  • We will set up an evaluation account that gives the permission to receive support directly from our technical team. Cendio can also provide trial licenses for more than 10 users. Please contact directly.

  • Cendio wants to sponsor organizations where the business aims to make the world better. This means to help people, regions etc. that really need help. Please contact us a

  • Cendio offers a non-profit discount for organizations that fall under the definitions that can be found at the following link. Please contact us at for pricing. 

  • Cendio will, in good time before expiration of the ThinLinc Subscriptions Agreement, send a reminder by email. The renewal process will follow the same routines that are used in a new or additional purchase.

  • Other set-ups are possible for bigger deals. Contact

  • Purchases can be done directly via invoice, web shop or by a reseller. Cendio is a Swedish and EU company with long experience from doing business with foreign organizations. If you have any questions or need support, please contact us at

  • Best functionality and performance will always be achieved by upgrading to the latest version, both on the server and client-side. A newer version on the client-side will always give a better user experience than a former version. Cendio’s ambition is to keep good compatibility and functionality between the different versions. Historically, good compatibility between versions has been 3-5 years.

  • A ThinLinc set-up consists of a server software, client software and user licenses.

    Server software

    The server software is the heart of ThinLinc installation and handles all sessions, desktop environments and generates the virtual desktop, workspace etc.

    User licenses

    To allow more than 10 sessions to connect access to the server software, user licenses need to be added into the server software. User licenses are bought from Cendio. Please note, when placing user licenses into the ThinLinc server, the counting starts from 0, not 10. In concrete, this means that you need to buy and install the number of user licenses that you need.

    Client software

    The client software is installed on the device that is used to connect to the server and provision the virtual desktop / workspace. If using the web access client, no local installation of client software is needed, the provisioning is generated via the web browser that is installed at the server.

  • It’s up to the licensee to decide who can connect into the server installation. The ThinLinc client software is free of charge and can be downloaded by everyone.

  • The licensing is per organization. There is no limitation on how the ThinLinc user licenses are distributed in the legal organization, as long as the number of consumed licenses don’t exceed the number of paid licenses. It’s allowed to move the user licenses, but not copy.

  • The license use can be seen in the status module, how to manage can be found at . ThinLinc will notify you when the limit of licenses has been reached, for detailed information see,

  • Both the ThinLinc server and client software are free to distribute. The user licenses are connected to a purchase and are not allowed to distribute. For more detailed information, see

  • A specific version of ThinLinc is supported 3 years from release date. After 3 years, Cendio can’t guarantee support.

  • The number of user licenses that will be delivered will be in accordance with the number of subscriptions that have been acquired by the customer. The user licenses are perpetual.

  • When adding user licenses into the ThinLinc server, the counting will start from zero. So if you require 200 users, you need to have 200 user licenses

  • You need to buy user licenses and install them in the ThinLinc server. The user licenses are received through buying ThinLinc subscriptions.

  • It’s easy to add new users into a current ThinLinc set-up. By purchasing additional subscriptions into your agreement, so will we issue additional user licenses.

  • Cendio will, after receiving a valid order, distribute user licenses via email for the latest version after a purchase. If the purchase is a renewal and the customers have already received the latest version, no user licenses will be delivered by default, updated licenses will be delivered on request in this case.

  • It’s possible to merge existing agreements. When doing a merge, the period shall be at least 12 months.

  • The default rule is that the prices are set in accordance with the number of subscriptions that are purchased at the actual call off. Deviation from this can be eventually agreed if a roll-out plan can be committed in advance.

  • The client software packages are free of charge.

  • The ThinLinc license is perpetual and will still work after the expiry date of the ThinLinc subscriptions.


  • Both as an individual and as an organization, it is not allowed to use the free version of ThinLinc if you have valid user licenses.

  • ThinLinc is free to use for up to 10 concurrent users for both individuals and organizations (on a group basis).

  • ThinLinc Subscriptions give the possibility to run more than 10 concurrent users per ThinLinc installation. It also gives technical support directly from Cendio and the right to get upgrades (new versions) for ThinLinc.

  • ThinLinc Premium Subscription gives prioritized answers, faster response time, and direct access to our qualified technical support via telephone service.

  • The free version of ThinLinc is limited to 10 concurrent users and is supported via the ThinLinc Community. The commercial version of ThinLinc is packaged in a so-called subscription and can be scaled for more than 10 users. The subscriptions also give the right to get professional support in ThinLinc directly from the Cendio technical team.

  • ThinLinc is free to use up to 10 users at the same time per individual or organization worldwide, without any obligations. The usage can be 10 installations with one user per each or one installation with 10 users. What matters is that the 10 users aren’t exceeded.

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