qiime demux emp-paired Invalid value for '--i-seqs': Expected an artifact of at least type


I am trying to run the following commands but it gives errors.

*qiime demux emp-paired*
--i-seqs /home/mpolat/ANALYSIS/Qiime2/salt_experiment/qiime_analysis/sequences.qza
--m-barcodes-file /home/mpolat/ANALYSIS/Qiime2/salt_experiment/metadata.txt
--m-barcodes-column sampleid
--o-per-sample-sequences demux.qza
--o-error-correction-details demux-details.qza

(1/2) Invalid value for '--i-seqs': Expected an artifact of at least type
** EMPPairedEndSequences. An artifact of type**
** SampleData[PairedEndSequencesWithQuality] was provided.**
** (2/2) Invalid value for '--m-barcodes-file': There was an issue with**
** retrieving column 'sampleid' from the metadata.**

Hello and welcome to the forums, Air Bender. :tornado: :qiime2:

Here are the two errors and how I might try to fix them:

An artifact of type SampleData[PairedEndSequencesWithQuality] was provided.

One of two things happened:

  1. Your data is already demultiplexed: If your sequences have already been demultiplexed you don't have to import them. You can go to the next step!

  2. Your data is in another format: If you don't have EMP data, use one of the other formats listed here: Importing data — QIIME 2 2023.9.2 documentation

There was an issue with retrieving column 'sampleid' from the metadata.

Does your metadata file have a column called sampleid?

You can run
head /home/mpolat/ANALYSIS/Qiime2/salt_experiment/metadata.txt
and post a few lines to help us check.


Hello again,

My data was already demultiplexed, you were right. Thank you for the quick answer.

However, I would like to know if my metadata.txt is correct for further analysis.

I did my table in Excel and imported it as a tab-separated text file.

That should work well. Qiime2 will validate the metadata file each time it's used and alert you of major errors. You can add columns to your metadata file later in the analysis too.


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