Knowledgebase : Active Sky XP

Many users have requested clarification on which add-ons are compatible and which are potentially in conflict when using ASXP.

We've created this article to clear things up and provide further insight into the potential for conflict.  This is an "in-progress" article that will be updated as we learn more and can provide further guidance.

Firstly, it is important to note that ASXP is not a traditional wx add-on product for X-Plane.  Terms like "engine", "injector", "script", have been used to describe certain add-ons and their method of weather "control".  Active Sky has been considered a "weather engine" for 2 decades, with the term "weather engine" meaning that it creates weather in the simulator.  This "weather engine" term has evolved over the years and it's meaning diverged depending on platform and use of this term by other products, but in the scope of Active Sky, "weather engine" refers to any add-on or script that controls weather. 

To avoid further confusion, we'll refer to "weather engines" as "weather add-ons" within this article.  Any product, add-on, script, tool or program that attempts to inject weather, control it at any level, or augment it, is considered a "weather add-on".

Different weather add-ons can control the weather at different levels.  In the case of some LUA scripts for example, they attempt to enhance or control turbulence and/or crosswinds.  This is partial weather control.  Other add-ons can provide simple levels of "METAR injection" which more fully control the weather, intending to simply inject live data into the simulator.  More comprehensive add-ons, such as ASXP, use detailed synthesis and realism modification, multiple and/or hybrid approaches to weather depiction, and use multiple API mechanisms for different parts of weather control, controlling the weather in high detail at high frequency.  There is also another class of weather add-ons which completely replace the entire X-Plane graphics/visuals in regards to weather/clouds depiction, and similarly control the weather in high detail.

In regards to weather add-ons, ONLY ONE can be installed/active at a time.  Use of more than one will surely result in conflict and unwanted interaction.  For example, a simple LUA script or add-on intending to slightly enhance turbulence may take complete control of the weather environment, unintentionally, by setting what is known as "weather DataRefs" (one of the API tools available in X-Plane).  If a program like Active Sky is also installed and active, the weather mode will become mis-synchronized every time the turbulence script/add-on tries to control the turbulence level.  This results in completely wrong depiction and loss of control of weather by Active Sky.

Products/add-ons we consider a "weather add-on", of which only ONE can be installed/activated for proper weather depiction include, but are not limited to: xEnviro, FSGRWX, XWindHandling LUA script, Turbulence Enhancer LUA script and NOAA weather.

Please make sure only ONE weather add-on is installed/activated at a time to enjoy proper weather depiction as the add-on intends.

There are also some products which are not primarily weather add-ons, but have weather add-on features and similarly attempt to control the weather.  With these add-ons, it is important to TURN OFF any weather controlling/enhancing features.  Products/add-ons we are aware of that match this description include VATSIM or other ATC network client software (when weather control is enabled).

Please make sure to DISABLE any weather add-on features in such add-ons to avoid unwanted interaction and improper depiction.

Any conflict/interaction issue can result in: Improper weather depiction, wrong or missing winds, lost aircraft position, X-Plane or add-on stability/crashing issues, high CPU utilization issues and much more.  When experiencing any problem like this, it is very important to consider conflicts and take inventory of your add-ons, ensuring a conflict-free environment.

There is another class of add-on which we'll call "Visual Enhancement add-ons".  These do NOT attempt to control the weather at any level, and instead enhance/replace certain content/graphics/artwork/shaders that is visible/affect visuals in the simulator.  These add-ons work OK with ASXP and any other weather add-on.  Visual Enhancement add-ons include, but are not limited to: Ultra Weather XP and Reshade, and many other freeware and commercial add-ons (clouds, sky, water, etc.) that enhance visuals without controlling weather.  These add-ons can and usually do affect the realized depiction in various ways, but do not attempt to control the weather itself.  Therefore, there are no conflicts.

Regarding some weather-addons mentioned earlier, which completely replace the entire X-Plane graphics/visuals for weather/clouds depiction: These can also be Visual Enhancement add-ons (combination weather + visual enhancement).  In this case, however, these add-ons are visually enhancing the content of their own replaced visuals, not the general simulator content/graphics/artwork/shaders.


  • Active Sky is considered a "weather add-on" and has also been called a "weather engine" that synthesizes and creates weather based on real data for maximum realism within the simulator, using a variety of weather control tools and mechanisms in a hybrid depiction/injection approach
  • Only one weather add-on can be installed/active at a time
  • Several scripts/add-ons have weather-addon features which, if enabled, make the add-on a "weather add-on", and will conflict
  • Visual enhancement add-ons do not conflict
  • Conflicts results in many issues including invalid weather conditions, missing or invalid winds, crashing/stability issues, high CPU utilization and much more
  • When experiencing any problem in the above categories, an inventory of add-ons should be performed and a conflict-free environment needs to be established/confirmed

Error: Crash/error on startup of any Active Sky product (FileNotFoundException referencing _nLoad)


We have had a few reports recently from false-positive via Microsoft Windows Defender where detection will initiate on temp files created by what appears to be standard .NET operations.  We have confirmed multiple times that no malware exists and have repeatedly sent files for analysis to Microsoft, where it will clear, but then come back occasionally for some users.  During updates of our products, we notice a higher frequency of these issues since it appears the previous "whitelisting" of our software is no longer valid for the new version and must undergo this new "whilelisting" process.  

We apologize for the inconvenience, however this is beyond our control and apparently due to aggressive "code detection" with false-positives.  There are several solutions to resolve this:

1) Please ensure your Windows is up to date with all the latest updates

2) Ensure that Windows Defender has been updated with latest virus definitions

3) Uninstall Active Sky, remove any "quarantined" items from Windows Defender

4) Reinstall Active Sky

These steps will usually allow Active Sky to run properly without further issues.

If the issue continues, the following steps will allow the product to run:

1) In Windows Defender, either allow the detected threat or exclude the found item.  See this link for details:

2) It is recommended to submit the detected threat to Microsoft to have them analyze and whitelist/clear this software accordingly to prevent this from happening in the future.  You can submit threats for analysis here:

If you are unable to obtain resolution with the above steps, please open a new ticket with details and we will assist directly.


In some cases, running ASXP and X-Plane will result in crashing in X-Plane, usually right at the start of the flight or sometime shortly after the start of the flight.


We have identified one potential issue related to a bug in ASXP which has already been corrected and posted as 6919B update, available at our downloads page:

Another rarer issue has been found where the local X-Plane installation is a mixture of normal download X-Plane version and Steam version.  This can be caused by an attempted move/upgrade from one type to the other, or using certain "steam emulator" software.  In any case, the mixing of Steam and X-Plane versions is not supported with ASXP and can cause many problems both in ASXP and in general.

Finally, we have found that some aircraft that have not been properly updated to 11.30 compatibility are causing issues running X-Plane 11.30 beta version, regardless of ASXP or not.  


1) Update to 6919B if not already done:
2) If a mixed Steam/Normal installation exists, please correct this by either reinstalling X-Plane, or manually removing the steam-related files out of a non-steam installation, or vice verse.
3) If using 3rd party aircraft not yet confirmed compatible with X-Plane 11.30, and you are using 11.30 beta version, please use a different aircraft

Keywords: Shutdown, immediate close, opens then closes, connection issue, modified HOSTS file

We have found that certain unauthorized versions of Active Sky (including previous version for other platforms) can modify system files, potentially install malware on the user's system, and attempt to spoof servers that Active Sky connects to.

If you have installed an unauthorized version of Active Sky, and subsequently attempt to run a legitimate licensed version of Active Sky, you may be subject to this issue.  This issue can be confirmed by reviewing your HOSTS file located at:

If any "" or "" entries exist here, this confirms the spoofing and redirection of our servers which will not be able to connect.  If your system is affected by this, it is due to installing unauthorized software and the unauthorized system modifications it makes to attempt to bypass licensing and break into our data services.  Malware and other unintended negative changes on your system are common issues when using unauthorized software.

If you have purchased a valid license of Active Sky and are affected by this issue, please reset/clear your HOSTS file.  You can refer to this Microsoft support article for instructions:

After clearing the HOSTS file, we also recommend repairing and/or reinstalling Windows to clear any other potential malware/system changes that this previous unauthorized version may have installed.

Dear customers,

Please note we are unable to answer requests for help that are posted in the comments area of our Knowledgebase.  While we appreciate all customer feedback we cannot answer specific support requests as there is no way of contacting our users through the Knowledgebase.

We ask that customers post their issues in the community forum or request direct support via our ticket system which can be reached at:

Thank you for your assistance, we look forward to hearing from you.

The HiFi Support Team.

Keywords: auto, switching, manually configured, X-Plane, ASXP


When attempting to use default theme mode of ASXP, and the appropriate "From custom METAR.rwx" mode in X-Plane, X-Plane automatically switches modes to Manually Configured, resulting in improper weather depiction.


This is usually caused by other add-ons attempting to control weather, completely or partially, conflicting with ASXP and the weather mode.  Some add-ons have turbulence enhacements (XP Realistic Pro) for example, which automatically control the weather mode and certain weather aspects when turbulence enhancement is enabled, and will conflict.

Auto switch to Manually Configured can also occur when ASXP's mode has been set to Global Static, as Manually Configured is the appropriate XP weather mode for this ASXP depicition mode.  


1) Disable or remove other weather-controlling add-ons and/or weather features such as turbulence effects in those add-ons

2) Use default theme mode of ASXP by unchecking "Enable Global Static depiction mode" in ASXP Options (Simulator Depiction Options)