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Detailed Release Notes for PRTG 9.1.x in 2011



This article shows the detailed changes in PRTG 9.1.x since the official release on Sep 19th 2011 (until end of 2011).

bugfixes changes prtg prtg9 release-notes

Created on Oct 11, 2011 2:48:02 PM by  Dirk Paessler [Founder Paessler AG] (11,025) 3 6

Last change on Apr 4, 2012 10:47:12 AM by  Daniel Zobel [Product Manager]

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Accepted Answer



Note: For the latest version 9 release notes, please see the official website:

PRTG Network Monitor 9 Version History

December 15th 2011 - Version

  • New: [WebGUI] Added a “Property Sheet” on the “Management” tab of groups/probes. You can now select one or more objects from the device tree and edit their settings in one place
  • New: [Core] You can now allow “read-only users” to acknowledge alarms (this is a user account setting)
  • New: [Core] You can now promote users of any PRTG user group to admins (this is a user group setting, if enabled all users of a group are admins). This means that you can now also manage PRTG admins in the Active Directory, too, by creating an AD based group in PRTG and giving this group admin rights
  • New: [EC] Added “View Point” feature. When you start the EC you will be taken back to the same screen/tab/element that was viewed before the previous EC shutdown
  • New: [EC] Added features “Add Library”, “Add Map”, “Add Report”
  • New: [Core] In complex Active Directory environments (>100 AD groups) user must now enter group names manually (it took too long for PRTG to enumerate all groups for display purposes)
  • New: [Sensors] xFlow sensors can now filter packets using DNS names and IPs
  • New: [Autodiscovery] Autodiscovery uses proxy settings of parent object
  • Bugfix: [Core] After an upgrade from V8 to V9 some users ended up with a default configuration because folder paths were moved incorrectly
  • Bugfix: [WebGUI] Some users could not connect to the web interface (web server could not be started, reason “(unknown)”, PRTG had incorrectly used some disabled IPs of currently inactive network connections)
  • Bugfix: [Maps] Several fixes for the map display
  • Bugfix: [Sensors] Fixes for the sensor factory (1. problems with option "If a sensor has no data... Calculate the factory channels and use zero as source value", 2. Triggers did not work properly)
  • Bugfix: [Sensors] Updated DLLs for SQL sensors (MySQL, MSSQL, Oracle), improved support of recent sql server versions
  • Changed: [Probe] Stability improvements for the probe (improved scheduler, better WMI handling, watchdog for the probe scheduler)
  • Improved: [Notifications] PRTG’s outbound SMTP email system now retries DNS queries for MX records several times if necessary
  • Improved manual

November 28th 2011 - Version

  • New: [WebGUI] Sensor cross reference is now available "by tag" and "by type"
  • New: [Core] You can now create Active Directory groups with read-only users (only applies to new user accounts)
  • Changed: [Maps] Map object „sizeable status icon on status related background” now works for all object types (probes, groups, devices, and sensors)
  • Bugfix: [Core] Cloned default objects can now be deleted later
  • Bugfix: [Sensors] Fixed syslog receiver filtering
  • Bugfix: [WebGUI] On some platforms the sound notifications of the WebGUI did not work (i.e. iPad)
  • Bugfix: [EC] Probe nodes could not be sorted
  • Bugfix: [EC] EC freezes sometimes after alarm popup
  • Bugfix: [EC] decrease exception logging entries
  • Minor changes and updated manual

November 23rd 2011 - Version

  • New: [Maps] You can now select a background color for a map
  • New: [EC] One-click install of new software version if a core server runs a different version of the PRTG
  • Changed: [WebGUI] removed automatic refresh from search results to allow paging and sorting in tables
  • Changed: [Sensors] HTTP SSL Certificate sensor now uses proxy setting of device
  • Changed: [Sensors] HTTP Advanced sensor now has a User Agent String setting
  • Changed: [Sensors] Improved SQL sensors
  • Bugfix: [EC] Custom Packet Sniffer sensors did not display toplists in the EC
  • Minor changes and updated manual

November 14th 2011 - Version

  • Improved: [Maps] All map objects can now have an associated link, you can either enter an external link or select a device tree object or a another map as link
  • Improved: [Sensors] Improved connection handling for all WMI sensors, especially for WMI overload situations or whenever a target computer was rebooted
  • Improved: [Sensors] HTTP XML sensor is now more relaxed when a web server’s HTTP headers do not conform properly to the RFCs
  • Improved: [WebGUI] Various speed improvements for the device tree display
  • Improved: [Sensors] Rewrite of the INI file sensor for improved connection handling and better rights management (you must create new INI file sensors to use the new engine, existing sensors stay untouched)
  • Improved: [EC] Enterprise Console can now connect to a core server even if port 80/443 is not set correctly
  • Improved: [EC] Various minor changes and fixes for the Enterprise Console
  • Bugfix: [Maps] Some minor bugfixes for the map editor
  • Bugfix: [WebGUI] Links for switching to other cluster nodes (“home” menu) had been incorrect when a site name was entered in the web site settings
  • Bugfix: [Core] Fixed access violations that were written to the core server log when a library was viewed on a failover node
  • Changed: [Core] After a restart of the core server it may now take a little longer than in previous versions until all sensors are green. This is due to an internal change required for more reliable trigger definitions. The monitoring behavior and results have not changed, only the display.
  • Changed: [Sensors] WMI Event Log sensor now only supports scanning for one event id per sensors (performance optimization)
  • Changed: [Sensors] All http sensors do not support gzip/deflate compression (as defined by http/1.1) any more (performance/stability issue)
  • Changed: [Debugging] You will get extended profiling information on the WebGUI if you add a “&showtiming=1” to any URL

October 20th 2011 - Version

  • New: [Enterprise Console] Various improvements (speed and usability)
  • New: [WebGUI] Redesigned startup screen
  • New: [WebGUI] Alarmsound in browsers does not require Quicktime any more
  • New: [Core] Active Directory integration now supports Universal Groups
  • New: [Notifications] SMS notification now also accepts HTTP response code 204
  • Bugfix: [Core] Fixed potential crash of core server service due to toplist database problems
  • Bugfix: [Probe] Fixed potential crash of probe service due to HTTP sensors using https with http/1.1 and gzip-compression
  • Bugfix: [Probe] Fixed potential crash in the probe with http sensors
  • Bugfix: [Probe] Calculation of the delay values in the probe heath sensor
  • Bugfix: [Translations] Fixed misspelled strings for multi-byte languages
  • Bugfix: [Sensors] sFlow did not always show all traffic of a port
  • Bugfix: [Sensors] fixed scan of available SLAs of IPSLA sensor
  • Bugfix: [Sensors] When upgrading from V8 to V9 channels of packet sniffer sensors got duplicated sometimes
  • Bugfix: [Sensors] Fixed a handle leak in File sensor
  • Bugfix: [Sensors] Creating several MSMQ sensors at once works now
  • Bugfix: [Sensors] WMI SQL Server Buffer Manager Counters fixed. Percentage of "Chache Hit Ratio" was inverted.
  • Bugfix: [Enterprise Console] Notifications tab was not accessible for probes
  • Bugfix: [WebGUI] French localisation

October 11th 2011 - Version

  • New: [Sensors] SNMP Traffic sensors can now use the “ifDescr” field as port identification (this is a new device setting)
  • Improved: [WebGUI] Alarmsound in web browser doesn’t require Quicktime installation anymore
  • Bugfix: [WebGUI] Users upgrading from V8 got a “Sorry, the selected object cannot be used here” error when they had one of the dashboards configured as their home page
  • Bugfix: [Auto-Discovery] Some Windows systems were incorrectly tagged as “Exchange Server”
  • Bugfix: [Sensors] HTTP sensors sometimes crashed when they were monitoring a HTTP url that redirects to HTTPS
  • Bugfix: [EC] Fixed Save, delete and edit for toplists
  • Bugfix: [EC] Various drag&drop fixes
  • Bugfix: [EC] Toplist tab was not visible for netflow/sflow/jflow/packet sniffer sensors
  • Bugfix: [Core] Sometimes the data cache was recalculated too often
  • Various minor improvements and fixes

October 6th 2011 - Version

  • New: [Sensors] New sensor type “Windows Scheduled Task”
  • Improved: [Sensors] When creating new Windows MSMQ Queue Length Sensor and Windows Print Queue Sensor you can now select queue from a list of available queues
  • New: [Maps] New map object resizable colored icon, see knowledge base
  • Bugfix: [Core] Fixed a bug where users were getting gray (unknown) sensors when they folded up/down a group at an unfortunate moment
  • Bugfix: [Core] Fixed a bug where an autodiscovery scan could bring down all SNMP sensors
  • Bugfix: [Reporting] Reports PDFs in landscape orientation did not always work properly
  • Bugfix: [Enterprise Console] Drag&Drop of devices did not work reliably
  • Bugfix: [WebGUI] Fixed various encoding issues for multi-byte languages
  • Changed: [Enterprise Console] Various improvements based on user feedback
  • Changed: [WebGUI] Tightened security (e.g. non-admin users can not view data on the Status page any more)
  • Various smaller changes, fixes and an updated manualBugfix: Fixed a validation error for active directory settings without domain

September 30th 2011 - Version

  • Bugfix: Fixed a validation error for active directory settings without domain
  • Bugfix: Using the same license key on two cluster nodes failed in some situations
  • Bugfix: Under certain conditions channel limits were overwritten by defaults
  • Bugfix: [Maps] Map editor did not load in Firefox on some installations
  • Bugfix: [Sensors] Fixes for SNMP V3
  • Bugfix: [Sensors] Fixes for sFlow
  • Bugfix: [Sensors] In some cases Ping sensors showed "up" status where they should have shown "down" status
  • Bugfix: [Sensors] Fixed WMI HyperV Network Sensor
  • Bugfix: [Sensors] Some channel setting were overwritten with defaults upon restart
  • Bugfix: [Autodiscovery] Fixed incorrectly assigned "Xerox" icons
  • Bugfix: [Enterprise Console] Fixed access violations
  • Bugfix: [Enterprise Console] Live graph was not correctly displayed
  • Bugfix: Autoupdate did not work on some freeware/trial installations

Created on Oct 11, 2011 2:49:55 PM by  Dirk Paessler [Founder Paessler AG] (11,025) 3 6

Last change on Apr 4, 2012 10:50:16 AM by  Daniel Zobel [Product Manager]

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.