diff --git a/README.md b/README.md
index 5eb0d21..313081a 100644
--- a/README.md
+++ b/README.md
@@ -79,7 +79,7 @@ To aid the use of SQLite mode with persistent data, the default configuration ha
 docker run -d --name opensim -p 9000:9000 -p 9000:9000/udp -v /path/on/your/system:/opt/opensim/bin/sqlite-database  soupbowl/opensimulator:latest
 ```
 
-# Limitations
+# Limitations and Troubleshooting
 
 ## Physics in ARM
 
@@ -96,6 +96,10 @@ Alternatively, a suitable drop-in library in `lib64/libBulletSim-aarch64.so` for
 
 **I'm keen to support ARM architecture to the bounds of OpenSimulator. If you have any experience on this, please reach out to me.**
 
+## `Command error: System.NullReferenceException: Object reference not set to an instance of an object.`
+
+This occurs because the terminal is expecting a method of input, but isn't able to detect one. This is why the command requires `-it`, and the compose needs `tty` and `stdin_open`.
+
 # Examples
 
 See [this repository](https://github.com/soup-bowl/opensim-sandbox) for some example usages of this image.