Since approximately the last week of October 2017, several users have reported a problem where ASP4 (Active Sky for Prepar3D v4) or AS16 (Active Sky 2016, For FSX or for P3D v3) fails to start. The window does not open and nothing appears to happen.
We have numerous confirmations that some Anti Virus software has been blocking AS, and adding an exclusion (which allows the program to operate) will resolve the issue in such cases. AVG specifically has been common in this regard. Please see your AV software manual or search for "Excluding Applications in XXXX AV software" for instructions. The exclusion settings are usually a main configuration item available from your AV software's main application screen. For AVG, see this article for instructions: https://support.avg.com/SupportArticleView?l=en&urlName=How-to-exclude-file-folder-or-website-from-AVG-scanning&supportType=home
The items that should be excluded:
The application itself, i.e. [Active Sky Install folder]\AS_P3Dv4.exe or AS16.exe
The simulator i.e. [Simulator install folder]\Prepar3D.exe or FSX.exe
The ASConnect module folder i.e. [Simulator install folder]\as_srv
In some cases, your AV software may not allow exclusion of an entire folder. In that case we recommend excluding the module .dll itself which is [Simulator install folder]\as_srv\as_connect_64.dll (for ASP4) or as_btstrp.dll (for AS16).
Note that these exclusions may have to be re-added after updating Active Sky in the future.
We recommend that you contact your AV software provider to let them know of this "false positive" regarding Active Sky. We have already contacted the known false-positive providers, but they require that the licensed users contact them as well.
An alternative solution to this problem has also been confirmed by a few users: Check the "Compatibility Mode" option in compatibility/advanced settings for the AS_P3Dv4.exe or AS16.exe application, and choose "Windows 8". This may be helpful for those having trouble adding the exclusions in their AV software.
If you continue having problems after ensuring that the above items are excluded, and/or Compatibility mode enabled, please open a support ticket and include as much information as possible including your AV software type/version and a screenshot or details regarding your exclusions.