ISL AlwaysOn 4.4.2526.58 for Windows, macOS and Linux (2025-10-02)
General Information
On 2nd of October the following was released:
- ISL AlwaysOn 4.4.2526.58 for Windows (release_date=2025-09-28, build=7be461a7b231531db2c32214529680b3c627697a, platform=win32, os_version=0x06010000-0x7fffffff)
- ISL AlwaysOn 4.4.2526.58 for macOS (release_date=2025-09-28, build=7be461a7b231531db2c32214529680b3c627697a, platform=mac, os_version=0x0a0e00-0x1bffff)
- ISL AlwaysOn 4.4.2526.58 for Linux (release_date=2025-09-28, build=7be461a7b231531db2c32214529680b3c627697a, platform=linux64, os_version=0x030a000000021100-0xffffffffffffffff)
All updates have release date set to 2025-09-28. Your ESS will need to be same or higher to be able to update your server. This release is available to all countries except Japan.
Upgrading to new version
Hosted service users please check Upgrading Hosted Service.
Server license users please check Upgrading Server License.
Improvements
Description
The libdatachannel and libjuice library were updated to latest version (libdatachannel-0.22.2 and libjuice-1.5.7).
Description
Internal mbedTLS library was updated to version 2.28.10.
Description
In previous version all ISL AlwaysOn watchdog crashes were uploaded to ISL Conference Proxy, but they do not have enough useful information. We have limited watchdog crash reports to upload 2% of reported crashes to the ISL Conference Proxy
Description
Updated location where ISL AlwaysOn service minidumps are saved. Files are now saved in the ISL AlwaysOn installation directory.
Description
Watchdog implementation of Windows was updated with:
- updated timeouts
- added log for thread ids
- added NOX on failed thread create
- removed use of rand function that uses enter critical section
The time for unresponsive scheduler check is 2,5 min - before it was 2min. The time for unresponsive watcher check is now 10 min - before it was 2min. We now report also the wd count that was reached when watchdog crashed.
Description
We have added a new feature that changes the implementation of internal function that merges translations. The speed of this function is now measured in metric .language.load_time.
We have also moved loading of language file in thread that is preparing a plugin. Before the language file was loaded just before loading plugin.dll into a process on main thread. This reduced the UI delay when loading a plugin.
Description
AutoTransport methods wsstun-direct, wsstun-proxy, https-direct, https-proxy were fixed to use SNI (send connection hostname in SSL handshake) in order to improve compatibility with third party load balancers like Cloudflare.
Description
The log line of ISL Light now includes ecdh_ctx log key which shows which algorithm was used to establish the shared secret.
Description
Per product specific text escaping functionality was moved to unified implementation of text escaping.
Description
The desktop plugin implementation on ISL AlwaysOn (using ISSC) was adapted in order to work correctly on ISL Light Desk/Client.
Description
LZMADecode was removed from hefa-rpt and XZ is now included as a default in all builds of hefa-rpt.
Description
ISSC msg executor was updated, now the executor window stops after the main loop has been stopped. Additionally ISSC window handler VM_DESTROY was also improved.
Description
The desktop plugin implementation on ISL AlwaysOn (using ISSC) was further adapted in order to work correctly on ISL Light Desk/Client.
Description
Zlib library that is used in ISL AlwaysOn application was upgraded to version 1.3.1.
Description
Format of issc_decoder logs ( located in ISL Light log ) has been updated to include the id of the stream producing the log line.
Description
ISSC ZRLE codec was rewritten. The new implementation is simpler, clearer and allows further enhancements. This new implementation also improves performance of desktop sharing.
Description
Whiteboard implementation was updated. On All platforms the whiteboard is updated before showing/hiding. Before it was updated after show/hide operation. This fixes the issue with whiteboard flickering after manually clearing whiteboard and than restarting to draw.
On windows the whiteboard implementation is now using native GDI functions on all whiteboard. This improves whiteboard drawing speed.
Description
Enabled support for minidump of crashes to be written in Program Files folder instead of temporary folder. This temporary folder could get deleted so now since they are written in Program Files the minidump of crashes can be simply obtained.
Description
Innosetup was incorrectly using perl XML::DOM. This was replaced with XML::LibXML.
The defect was fixed.
Description
On Windows ISLAlwaysOn.exe, ISLAlwaysOnMonitor.exe and ISLAlwaysOnTray.exe were filled with incorrect information about version and other information, the icon was also missing. Populating meta data information was redesinged, correct information is now displayed.
The defect was fixed.
Description
In some cases the application crashed when checking for CPU features on Linux. Checking for CPU capabilites was redesigned, so the application will no longer crash.
The defect was fixed.
Description
Previously, all crash reports were sent to the server despite not containing enough information. We added crash report filtering to limit watchdog repots and only send the ones which contain enough information.
The defect was fixed.
Description
In ISL AlwaysOn about screen the Application name could overlap the logo in case the customers specified a long name. About screen was redesigned, application name is now wrapped, meaning if it is too long, it will display the name in multiple rows.
The defect was fixed.
Description
In case users had defined a customization for ISL AlwaysOn on Linux and it used a custom installation location, the default installation folder was still created. Handling of custom installation location was redesigned, the default installation folder is no longer created.
The defect was fixed.
Description
In certain cases desktop streaming stopped working. The operator log showed an issue with JPEG decoding due to incorrect JPEG encoding on the streaming side of the sent screen update which caused the streaming to stop. Libjpeg turbo was updated to version 3.1.0 and the issue with JPEG decoding was resolved.
The defect was fixed.
Description
The range of enum values was expanded when loading metrics from shared section. This resolves an issue with user action metrics, where ZRLE metrics from issc_stream ( external process) were not seen in the main application. Additionally a crash was fixed when dumping single UMA metric that has all buckets non-zero.
The defect was fixed.
Description
Users experienced an issue where the remote computers screen did not refresh correctly when there was no screen attached to the computer. The functionality was redesigned and the issue is no longer reproducible.
The defect was fixed.
Description
Users experienced an issue where they were unable to enable the restart&resume during a session. The issue was in ISSC Daemon timeout being reached. This timeout was increase and should no longer be causing inability to activate restart&resume.
The defect was fixed.
Description
The command clean and clean_silent was not working when uninstalling ISL AlwaysOn. The uninstaller got frozen and granted connections were not removed. Functionality was redesigned, the commands are now working correctly and user grants will be removed during uninstall if either of the clean commands is supplied.
The defect was fixed.
Description
Users experienced an issue where they were experiencing delays when connecting to ISL AlwaysOn computer in Windows Sandbox environment. The functionality was redesigned and the issue is no longer reproducible.
The defect was fixed.
Description
ISSC Daemon init procedure was moved to a later stage because ISSC daemon was initialized before flags were dumped. This improves readability of log and simplifies debugging.
The defect was fixed.
Description
Users experienced an issue where ISL AlwaysOn on Mac M series who have arm64 architectures, but run ISL programs with Rosetta, would report the Mac computers had x86_64 architectures, when natively they had arm64 architectures. The functionality was redesigned and the issue is no longer reproducible.
The defect was fixed.
Description
In previous versions the filename version was delimited with dots. This caused an issue when build number was less then 10 as the application opened as text editor. The dots were now replaced with underscores and this now always executes the application correctly.
The defect was fixed.
Description
In previous versions histograms that did not start with ASCII character were sent to the server. The functionality was redesigned and now only histograms that start with ASCII character are sent to the server.
The defect was fixed.
Description
Users experienced an issue where they were unable to enable Administrative Mode and Restart & Resume in session where they were connected to a machine with Windows Sandbox environment. The functionality was redesigned and the issue is no longer reproducible.
The defect was fixed.
Description
Some of the ISL AlwaysOn internal executables did not have correct information written in the details tab on Windows. Populating the information was redesigned, the internal executables should now have the correct version written in the details tab.
The defect was fixed.
Description
Users experienced an issue where sometimes Black screen status was not updated instantly upon enabling or disabling Black screen in session. The functionality was redesigned and the issue is no longer reproducible.
The defect was fixed.
Description
Users experienced an issue when using "Paste (simulate typing)" feature while in session as the pasted characters were not the same as they were in the shared clipboard. Functionality was redesigned and the issue is no longer reproducible.
The defect was fixed.
Description
In some cases when operators were controlling the remote macOS computer and typing into the remote computer something that required modifier keys, after typing those modifiers could remain stuck. Handling of modifier keys was redesigned, the keys are now correctly released after typing.
The defect was fixed.
Description
The ISL AlwaysOn application has incorrect copyright and version written in details. The details are now showing the correct copyright and correct version.
The defect was fixed.
Description
On macOS the resources could be injected to be copied by launcher to the destination folder. That was due to this operation being appended in the unsigned part of the package. The copy operation must now first be allowed in the signed part of the package in order to be executed in the unsigned part.
The defect was fixed.
Description
In previous version some mux connection channels were not protected by TLS session. TLS session is now enabled on all mux channels.
The defect was fixed.
Description
When connected from ISL Light Desk to ISL Light Client on windows and operator used pointer or marker tool, those marking were blinking when operator used 1:1 viewing option. Whiteboard tools now have faster updates which remove the blinking effect and the timeout of the drawing is now independent of other drawings meaning that each time you draw it will have different removal time.
The defect was fixed.
Description
The implementation of cursor grabbing when using polling driver was redesigned. When having increased DPI and the cursor is change to text input ( edit mode ) the correctly cursor along with the correct side is shown on the operator side.
The defect was fixed.
Description
On some systems ISSC Desktop Duplication driver could fail to retrieve DirectX device output. This resulted in ISSC (desktop sharing) crash. Handling of initialization of desktop sharing was redesigned, desktop sharing should no longer crash.
The defect was fixed.
Description
When controlling the remote machine, the remote mouse pointer was not hidden when using desktop duplication. The cursor of the client is now being grabbed using Win32 API when streaming side is using desktop duplication. The downside is that the cursor is always using 100% DPI which in effect could be shown smaller when remote side has increased DPI.
The defect was fixed.
We are now grabbing cursor with win32 api when streamer is desktop duplication.
caveat; streamed cursor uses 100% dpi
Description
The internal ISL AlwaysOn setup executable had incorrect version written in the details on Windows. Populating the meta data was redesigned, the correct version is now shown.
The defect was fixed.
Description
Handling of monitor switching was ported to ISSC, which now prevents crashing of application when operator is switching between monitors.
The defect was fixed.
Description
When multiple operator were connected to the same client and if operator 1 draw something on the client machine the operator 2 could not see the drawings. Implementation of whiteboard tools was improved, so all operators should see the whiteboard markings.
The defect was fixed.
Description
New implementation of desktop sharing plugin was improved, so the streamer is not sending whole desktop instead it's sending only the part that is viewed by the operator.
The defect was fixed.
Description
In some cases ISSC event handler on windows froze. Now it also checks for end flag instead of only wm_quit.
The defect was fixed.
Description
In some cases a no monitors attached driver was enabled when connecting to virtual machines. The application now checks if it's being run on virtual machine and skips no monitors attached driver if it detects it's being run on virtual machine.
The defect was fixed.
Description
When streaming desktop and receiving whiteboard events. If many events are received than local whiteboard might miss some events. Local whiteboard implementation was redesigned, the local whiteboard marking should be correctly displayed.
The defect was fixed.
