# Dropbox Error with Metaphlan while running tutorial for Humann

**URL:** <https://forum.biobakery.org/t/dropbox-error-with-metaphlan-while-running-tutorial-for-humann/5241>\
**Category:** HUMAnN\
**Created:** [May 7, 2023, 2:11am UTC](https://forum.biobakery.org/t/dropbox-error-with-metaphlan-while-running-tutorial-for-humann/5241 "2023-05-07T02:11:12Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Sal\_Lamsal](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.biobakery.org/sal_lamsal/32/2134_2.png) [@Sal\_Lamsal](https://forum.biobakery.org/u/Sal_Lamsal)\
**Post date:** [May 7, 2023, 2:11am UTC](https://forum.biobakery.org/t/dropbox-error-with-metaphlan-while-running-tutorial-for-humann/5241/1 "2023-05-07T02:11:12Z")

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Metaphlan 3.0

I encountered the following error message while running the tutorial for the Humann.

Following is the command i used and the error message.

humann --input demo.fastq.gz --output demo\_fastq --nucleotide-database /scratch/user/sal/Humann\_projects/humann\_dbs/chocophl  
an --protein-database /scratch/user/sal/Humann\_projects/humann\_dbs/uniref  
Output files will be written to: /scratch/user/sal/Humann\_projects/Tutorials/humann3/input/demo\_fastq  
Decompressing gzipped file …  
Running metaphlan …  
CRITICAL ERROR: Error executing: /scratch/user/sal/.conda/envs/Salenv/bin/metaphlan /scratch/user/sal/Humann\_projects/Tutorials/humann3/input/demo\_fastq/  
demo\_humann\_temp/tmpal5xx8vc/tmp295\_lrf4 -t rel\_ab -o /scratch/user/sal/Humann\_projects/Tutorials/humann3/input/demo\_fastq/demo\_humann\_temp/demo\_metaphla  
n\_bugs\_list.tsv --input\_type fastq --bowtie2out /scratch/user/sal/Humann\_projects/Tutorials/humann3/input/demo\_fastq/demo\_humann\_temp/demo\_metaphlan\_bowt  
ie2.txt  
Error message returned from metaphlan :  
Downloading [https://www.dropbox.com/sh/7qze7m7g9fe2xjg/AAA4XDP85WHon\_eHvztxkamTa/file\_list.txt?dl=1](https://www.dropbox.com/sh/7qze7m7g9fe2xjg/AAA4XDP85WHon_eHvztxkamTa/file_list.txt?dl=1)  
Warning: Unable to download [https://www.dropbox.com/sh/7qze7m7g9fe2xjg/AAA4XDP85WHon\_eHvztxkamTa/file\_list.txt?dl=1](https://www.dropbox.com/sh/7qze7m7g9fe2xjg/AAA4XDP85WHon_eHvztxkamTa/file_list.txt?dl=1)  
Traceback (most recent call last):  
File “/scratch/user/sal/.conda/envs/Salenv/bin/metaphlan”, line 10, in   
sys.exit(main())  
File “/scratch/user/sal/.conda/envs/Salenv/lib/python3.6/site-packages/metaphlan/metaphlan.py”, line 1187, in main  
pars[‘index’] = check\_and\_install\_database(pars[‘index’], pars[‘bowtie2db’], pars[‘bowtie2\_build’], pars[‘nproc’], pars[‘force\_download’])  
File “/scratch/user/sal/.conda/envs/Salenv/lib/python3.6/site-packages/metaphlan/metaphlan.py”, line 589, in check\_and\_install\_database  
index = resolve\_latest\_database(bowtie2\_db, ls\_f[‘mpa\_latest’], force\_redownload\_latest)  
UnboundLocalError: local variable ‘ls\_f’ referenced before assignment

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<div class="post-metadata">

**Author:** ![lauren.j.mciver](https://avatars.discourse-cdn.com/v4/letter/l/f05b48/32.png) [@lauren.j.mciver](https://forum.biobakery.org/u/lauren.j.mciver)\
**Post date:** [May 12, 2023, 3:39pm UTC](https://forum.biobakery.org/t/dropbox-error-with-metaphlan-while-running-tutorial-for-humann/5241/2 "2023-05-12T15:39:19Z")

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Hello, Thank you for the detailed post. If you update your MetaPhlAn install to the latest version, it should resolve the errors you are seeing.

Thank you,  
Lauren