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Wiki source code of Troubleshooting

Version 2.1 by kindler on 2021/05/03 16:11
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kindler 1.1 1 == Troubleshooting for the NMC system usage ==
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3 === Problems with the Jupyter notebook environment ("Lab") ===
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5 ==== Error message "Error in Authenticator.pre_spawn_start: ... 401: Unauthorized" ====
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7 To fix this error when starting the "Lab", please access the "Drive" link in the collab once (left hand navigation menu of the Collab)
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kindler 2.1 9 ==== No example notebooks in the Jupyter notebook environment ("Lab") ====
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11 When starting the Jupyter notebook environment for the first time it takes about a minute (without visible "in progress" indication) until the example files appear in the file-chooser. So the fix here is "have a minute patience"
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13 ==== Timeout when starting the Jupyter notebook environment ("Lab") ====
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15 It is possible, that accessing the "Lab" link results in a "timeout" message. This can happen, when the lab environment is started for the first time on one of the virtual machines providing the service, as the very first start per machine takes quite some time (in the order of 2 minutes). Accessing the "Lab" link again after a few minutes usually works.
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