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...	...	@@ -10,6 +10,23 @@
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11	11	== Jupyter notebook environment ("Lab") related ==
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	13	+=== Error message "RuntimeError: EBRAINS kernel mismatch. Expected: EBRAINS-24.04 Actual: EBRAINS-25.02. Please select the appropriate kernel." ===
	14	+
	15	+The BrainScaleS notebooks intended to be used with one of the "stable release" kernels in the EBRAINS Jupyter environment check for a specific kernel version (e.g. for EBRAINS-24.04). When a newer docker image is deployed on the EBRAINS application servers (like e.g. on 14 May 2025) several old kernels are not available in that new environment (e.g. due to incompatibilities with a newer Jupyter version). Then the BrainScaleS notebooks from the stable release branch in git can not run.
	16	+
	17	+Options to fix this:
	18	+
	19	+* use the notebooks from the "experimental" release branch of the BrainScaleS notebooks. These notebooks check for the "experimental" kernel name. They are also usually the recommended-for-use-of-BrainSclaeS one, as we frequently add features and fix problems for BrainScaleS.
	20	+To get the newest version of the experimental release ones use this git clone command in the Terminal (can be started via File > New > Terminal inside the Lab):
	21	+//git clone https:~/~/github.com/electronicvisions/brainscales2-demos.git ~-~-branch jupyter-notebooks//
	22	+
	23	+* or get a fresh copy of the stable release BrainScaleS notebooks from the git repository by using (this does only help after the repository has been updated after a change of the docker image):
	24	+//git clone https:~/~/github.com/electronicvisions/brainscales2-demos.git ~-~-branch jupyter-notebooks-experimental//
	25	+
	26	+* or change the name, the notebooks test for by hand (note: if there is an incompatible change in a kernel just changing the expected kernel name will of course not help. It will then only create an error further down in the execution).
	27	+** in the directory, where the notebook is stored, find the _static/common sub-directory
	28	+** in that open the file collab_helpers.py and change the check (around line 19)
	29	+
13	13	=== Error message "Error in Authenticator.pre_spawn_start: ... 401: Unauthorized" ===
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15	15	When a new user accesses the Lab in a new collab for the first time, it is possible, that the JuypterLab is not starting and instead shows a "...401 Unauthorized" message.