Add error description and example

samples/cpp/beam_search_causal_lm/README.md

@@ -17,9 +17,20 @@ optimum-cli export openvino --trust-remote-code --model TinyLlama/TinyLlama-1.1B
 
 `beam_search_causal_lm TinyLlama-1.1B-Chat-v1.0 "Why is the Sun yellow?"`
 
-To enable Unicode characters for Windows cmd open `Region` settings from `Control panel`. `Administrative`->`Change system locale`->`Beta: Use Unicode UTF-8 for worldwide language support`->`OK`. Reboot.
-Also, you can enable UTF-8 mode by setting environment variable `PYTHONIOENCODING="utf8"`.
 
 Discrete GPUs (dGPUs) usually provide better performance compared to CPUs. It is recommended to run larger models on a dGPU with 32GB+ RAM. For example, the model meta-llama/Llama-2-13b-chat-hf can benefit from being run on a dGPU. Modify the source code to change the device for inference to the GPU.
 
 See https://github.com/openvinotoolkit/openvino.genai/blob/master/src/README.md#supported-models for the list of supported models.
+
+### Troubleshooting
+
+#### Unicode characters encoding error on Windows
+
+Example error:
+```
+UnicodeEncodeError: 'charmap' codec can't encode character '\u25aa' in position 0: character maps to <undefined>
+```
+
+If you encounter the error described in the example when sample is printing output to the Windows console, it is likely due to the default Windows encoding not supporting certain Unicode characters. To resolve this:
+1. Enable Unicode characters for Windows cmd - open `Region` settings from `Control panel`. `Administrative`->`Change system locale`->`Beta: Use Unicode UTF-8 for worldwide language support`->`OK`. Reboot.
+2. Enable UTF-8 mode by setting environment variable `PYTHONIOENCODING="utf8"`.