Some common Bluestacks Problems:

Black Screen Problem:
I have been getting a lot of PM from you guys about this problem these days. Itís not difficult to fix this problem, just follow these simple steps:

  1. Firstly, try to click on the bottom center of the Bluestacks window, where the home button is present.
  2. Try to remove your Bluestacks fully with Your Uninstaller then install it again.
  3. If you are using Nvidia video card:
    1. Open Nvidia Graphics Card Settings
    2. Go toManage 3D Settings -> Program Settings -> Here Click on Add button -> Add Bluestacks Frontend.
    3. Turn off the Threaded Optimization line.
    4. At the tray icon, quit your Bluestacks.
    5. Open it again. It should run smoothly now!

  4. If you are using other video cards, try to update your video cardís driver to the latest version.

Failed to install Bluestacks problem:

  1. Cleanup all these folders:
    • C:\ProgramData\BlueStacks
    • C:\Program Files\BlueStacks
    • C:\Users\\AppData\Local\BlueStacks

  2. Download this tool for removing all old registry:
  3. Re-install the program again!

Error retrieving information from server.[RPC:S-5:AEC-0]
Another stupid common problems of Bluestacks! Follow these steps to solve this one:
Method 1:

  1. Open Bluestacks.
  2. Go to Settings ~> Applications ~> Manage Applications ~> Select All.
  3. Find and tap on Google Play Store ~> Force Stop.
  4. Clear Data ~> OK.
  5. Back, find, force stop and clear data of Google Service Framework.
  6. Reboot your device and it should be ok now!

Method 2:
If the first method does not work for you, please try this one: (Thanks Deconus for sharing this solution).

  1. Right Click on the Bluestacks in the system tray (right bottom).
  2. Choose Report Problem.
  3. Select RPC of the list problems.
  4. It will ask you to auto fix this problem, just click OK.
  5. Done. It should works fine now.

Source: Play Clash of Clans on PC with BlueStacks | Coc Land