# Unstable notebook failing after a reload or two: Any ideas why?

**URL:** <https://talk.observablehq.com/t/unstable-notebook-failing-after-a-reload-or-two-any-ideas-why/6645>\
**Category:** Help\
**Created:** [June 2, 2022, 6:34pm UTC](https://talk.observablehq.com/t/unstable-notebook-failing-after-a-reload-or-two-any-ideas-why/6645 "2022-06-02T18:34:51Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![JCL](https://yyz2.discourse-cdn.com/flex030/user_avatar/talk.observablehq.com/jcl/32/8898_2.png) [@JCL](https://talk.observablehq.com/u/JCL)\
**Post date:** [June 2, 2022, 6:34pm UTC](https://talk.observablehq.com/t/unstable-notebook-failing-after-a-reload-or-two-any-ideas-why/6645/1 "2022-06-02T18:34:51Z")

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I have a [notebook](https://observablehq.com/d/03ed731026e8a545) whose cells _randomly_ give errors:

It’s a hit and miss: sometimes it loads all OK, sometimes it loads with errors in many cells—usually a module error.

I tried running it in multiple browsers, in incognito mode, etc. to no avail; the problem persists.  
If you try to reload it a few times, you’d probably see the issue as well, but in case you don’t, here’s a screen recording (the errors appear after a reload or two):

> **[CleanShot 2022-06-02 at 20.18.55](https://share.cleanshot.com/J9bWCp)**
>
> Video uploaded to CleanShot Cloud

I suspect the issue could be related to the external data sources the notebook uses, but I’m not sure.  
After all, it gives a module error and not an error that seems linked to the data fetched.

I would greatly appreciate ideas and any tips on how this notebook can be made stable.

Many thanks in advance!

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**Author:** ![mbostock](https://yyz2.discourse-cdn.com/flex030/user_avatar/talk.observablehq.com/mbostock/32/9_2.png) [@mbostock](https://talk.observablehq.com/u/mbostock)\
**Post date:** [June 2, 2022, 7:01pm UTC](https://talk.observablehq.com/t/unstable-notebook-failing-after-a-reload-or-two-any-ideas-why/6645/2 "2022-06-02T19:01:22Z")

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It looks like you’re using an older version of @mootari’s range-slider notebook, which had an implementation of “lazy” imports that caused `require` to be unreliable. Try upgrading your import of that notebook (in the **Dependency versions** pane, or by clicking the lock icon next to that notebook), and try again?

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**Author:** ![tophtucker](https://yyz2.discourse-cdn.com/flex030/user_avatar/talk.observablehq.com/tophtucker/32/4781_2.png) [@tophtucker](https://talk.observablehq.com/u/tophtucker)\
**Post date:** [June 2, 2022, 7:02pm UTC](https://talk.observablehq.com/t/unstable-notebook-failing-after-a-reload-or-two-any-ideas-why/6645/3 "2022-06-02T19:02:18Z")

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yeah that fixes it for me 🙏

![BDB09315-0B33-4B0C-8C43-C7C174E2F891-853-000077804C6A16AA](https://canada1.discourse-cdn.com/flex030/uploads/observablehq/original/2X/b/bfcf130ca430543c6d5e7a673972d132334f1a69.png)

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**Author:** ![JCL](https://yyz2.discourse-cdn.com/flex030/user_avatar/talk.observablehq.com/jcl/32/8898_2.png) [@JCL](https://talk.observablehq.com/u/JCL)\
**Post date:** [June 2, 2022, 7:23pm UTC](https://talk.observablehq.com/t/unstable-notebook-failing-after-a-reload-or-two-any-ideas-why/6645/4 "2022-06-02T19:23:28Z")

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Thank you so much for the fast and dead-on answer Mike!  
It indeed worked and this was a life-saver.  
Very much appreciated!  
Good to know what to check next time something like this happens.

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**Author:** ![JCL](https://yyz2.discourse-cdn.com/flex030/user_avatar/talk.observablehq.com/jcl/32/8898_2.png) [@JCL](https://talk.observablehq.com/u/JCL)\
**Post date:** [June 2, 2022, 7:24pm UTC](https://talk.observablehq.com/t/unstable-notebook-failing-after-a-reload-or-two-any-ideas-why/6645/5 "2022-06-02T19:24:33Z")

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Thanks a lot for checking it—also fixes it here!