# Error Message

**URL:** <https://discourse.mc-stan.org/t/error-message/22195>\
**Category:** Modeling\
**Tags:** rstan\
**Created:** [April 29, 2021, 10:22am UTC](https://discourse.mc-stan.org/t/error-message/22195 "2021-04-29T10:22:00Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Him](https://avatars.discourse-cdn.com/v4/letter/h/82dd89/32.png) [@Him](https://discourse.mc-stan.org/u/Him)\
**Post date:** [April 29, 2021, 10:22am UTC](https://discourse.mc-stan.org/t/error-message/22195/1 "2021-04-29T10:22:00Z")

</div>

Please help me understand the following error message

```
Warning messages:
1: In system(paste(CXX, ARGS), ignore.stdout = TRUE, ignore.stderr = TRUE) :
  '-E' not found
2: There were 9 divergent transitions after warmup. See
http://mc-stan.org/misc/warnings.html#divergent-transitions-after-warmup
to find out why this is a problem and how to eliminate them. 
3: There were 71 transitions after warmup that exceeded the maximum treedepth. Increase max_treedepth above 10. See
http://mc-stan.org/misc/warnings.html#maximum-treedepth-exceeded 
4: Examine the pairs() plot to diagnose sampling problems
 
5: The largest R-hat is NA, indicating chains have not mixed.
Running the chains for more iterations may help. See
http://mc-stan.org/misc/warnings.html#r-hat 
6: Bulk Effective Samples Size (ESS) is too low, indicating posterior means and medians may be unreliable.
Running the chains for more iterations may help. See
http://mc-stan.org/misc/warnings.html#bulk-ess 
7: Tail Effective Samples Size (ESS) is too low, indicating posterior variances and tail quantiles may be unreliable.
Running the chains for more iterations may help. See
http://mc-stan.org/misc/warnings.html#tail-ess 

```

---

<div class="post-metadata">

**Author:** ![mike-lawrence](https://yyz2.discourse-cdn.com/flex030/user_avatar/discourse.mc-stan.org/mike-lawrence/32/59_2.png) [@mike-lawrence](https://discourse.mc-stan.org/u/mike-lawrence)\
**Post date:** [April 29, 2021, 6:03pm UTC](https://discourse.mc-stan.org/t/error-message/22195/2 "2021-04-29T18:03:47Z")

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So those are warnings, not errors.

I don’t know what this one is:

```
1: In system(paste(CXX, ARGS), ignore.stdout = TRUE, ignore.stderr = TRUE) :
  '-E' not found

```

But all the rest are [standard Stan warnings described here](https://mc-stan.org/misc/warnings.html).