Getting Unstuck
Help
Common Issues
Colab says "Warning: This notebook was not authored by Google"
This is normal. Click "Run anyway" to proceed. The notebooks are safe.
Qiskit installation is taking forever
Initial installation can take 30-60 seconds. If it exceeds 2 minutes, try Runtime → Restart runtime and run the cell again.
"ModuleNotFoundError: No module named 'qiskit'"
Run the first cell with !pip install qiskit qiskit-aer first. Make sure to wait for it to complete before running other cells.
Circuit diagram not displaying
Try qc.draw('mpl') instead of just qc.draw(). Make sure matplotlib is imported.
"No counts in result"
Make sure you have measurement operations in your circuit before running. Add qc.measure_all() before the simulation.
Results look wrong or unexpected
Quantum results are probabilistic. Run with more shots (e.g., 10000) to get more stable statistics. Also verify your circuit logic with the circuit diagram.
"You have exceeded your Colab usage limits" or running out of compute
Important: Close notebook tabs when you're done with each exercise! Each open notebook consumes computing resources. Go to Runtime → Disconnect and delete runtime before closing the tab, or simply close the tab and the session will eventually time out. If you hit limits, wait a few minutes or try a different Google account.
Keyboard Shortcuts (Colab)
| Shift + Enter | Run cell and move to next |
| Ctrl + Enter | Run cell and stay |
| Ctrl + M, B | Insert cell below |
| Ctrl + M, D | Delete cell |
| Ctrl + / | Comment/uncomment |
Still Stuck?
During the Workshop
Raise your hand! The instructor and TAs are here to help.
Check the Cheatsheet
The Cheatsheet has common code snippets and patterns.
Ask Your Neighbor
Pair programming and discussion often help clarify concepts.
Quick Debug Checklist
- □Did you run the installation cell first?
- □Are all previous cells completed (no spinning)?
- □Did you add measurements to your circuit?
- □Is the qubit/bit indexing correct?
- □Have you tried restarting the runtime?