15 Common errors and troubleshooting
This chapter covers
- The six most common errors when working with Ollama and Streamlit, along with their solutions
- A three-step method for reading any Python error message
- Defensive coding with try/except blocks, print debugging, and logging
- A troubleshooting checklist and flowchart
- How to ask for help effectively when you are stuck
Every programmer encounters errors. The difference between a beginner who gives up and a developer who ships software is not the number of errors they see; it is how quickly they can diagnose and fix them. Error messages are not failures; they are precise diagnostic information from the computer, telling you exactly what went wrong.
This chapter will build your diagnostic toolkit: you will learn to read error messages, isolate failures, and apply systematic fixes. These are skills that transfer to any programming language or framework.
15.1 Common errors and solutions
Let’s look at the six errors you are most likely to encounter. Think of this section as a field guide: the bigger your mental catalog of errors, the faster you can fix them.
15.1.1 Error: Model not found
This is the single most common error for Ollama beginners. You try to run a model, and Ollama tells you it does not exist:
ollama run llama3.2:3b Error: model "llama3.2:3b" not found, try pulling it first
The message is clear: the model file is not on your machine. Either you never downloaded it, or you typed the name incorrectly.