Eliminating the Persistent Black Box Around Mouse Cursor in FSX

Certainly, encountering unexpected graphical glitches after installing new content can be quite disconcerting. The black box you're observing around the cursor is a known anomaly that can occur under certain circumstances within FSX.

First, let's delve into the probable causes. This issue often stems from an incompatibility between FSX and certain overlays or graphical enhancements that may be part of the newly installed aircraft's package. It could be due to a conflicting add-on or a specific setting alteration within the sim's graphics configuration.

To address this, we should initiate a methodical troubleshooting protocol. Here’s a structured approach:

1. Check the FSX Settings: Navigate to the 'Settings' menu in FSX, and under 'Display', scrutinize the 'Graphics' tab. Ensure that the 'Light Bloom' effect is disabled, as this feature is known to cause issues with cursor display.
2. Inspect Add-on Aircraft Configurations: Review the documentation of the installed aircraft for any peculiar instructions or settings that need to be adjusted for optimal performance.
3. Update Graphics Drivers: Ensure your graphics card drivers are up-to-date. Outdated drivers can lead to various display issues within the sim.
4. Disable Background Applications: Occasionally, applications running in the background can interfere with FSX. Disable any non-essential programs, particularly those that feature an on-screen display or graphical overlay.
5. FSX.cfg File Tweaks: Locate your FSX.cfg file (usually found in your 'AppData' folder under 'Roaming\Microsoft\FSX'). Back it up first, then consider resetting it to default to see if the issue persists. Any custom settings will need to be reapplied after this step.
6. Revert to Default Cursor: As a last resort, within the sim, you could try switching back to the default cursor. While not ideal, this has resolved the issue for some users.

Remember, before making changes, always back up your files, especially when altering configuration files or settings. It ensures you have a recovery point should you need to revert.

Should these steps not resolve the issue, it might be helpful to gain further insights. Could you clarify if this occurs immediately upon launching FSX or only when loading the new aircraft? Also, details regarding the specific add-ons installed could shed more light on the compatibility aspects we may need to consider.

Do keep us updated on your progress, and should further assistance be required, rest assured, the community here is ready to lend a hand.

Happy flying!