Dada2 error message

Dear All
I have 38 paired end fastq files while I have uploaded to paired-end-demux.qza through manifest file. Now I wanted to apply Dada2 but I am getting error.

I am applying this command in qiime2019.4

qiime dada2 denoise-paired
–i-demultiplexed-seqs paired-end-demux.qza
–p-trim-left-f 10
–p-trim-left-r 10
–p-trunc-len-f 300
–p-trunc-len-r 300
–o-table table.qza
–o-representative-sequences rep-seqs.qza
–o-denoising-stats denoising-stats.qza
–p-n-threads 0

but I am getting below error message.

There was a problem with the command:
(1/1) Invalid value for “–i-demultiplexed-seqs”: ‘paired-end-demux.qza’ is
not a QIIME 2 Artifact (.qza)
Traceback (most recent call last):
File “/home/qiime2/miniconda/envs/qiime2-2019.4/lib/python3.6/”, line 624, in _exitfunc
File “/home/qiime2/miniconda/envs/qiime2-2019.4/lib/python3.6/”, line 548, in call
return info.func(info.args, *(info.kwargs or {}))
File “/home/qiime2/miniconda/envs/qiime2-2019.4/lib/python3.6/site-packages/qiime2/core/”, line 99, in _destruct
File “/home/qiime2/miniconda/envs/qiime2-2019.4/lib/python3.6/”, line 480, in rmtree
_rmtree_safe_fd(fd, path, onerror)
File “/home/qiime2/miniconda/envs/qiime2-2019.4/lib/python3.6/”, line 418, in _rmtree_safe_fd
_rmtree_safe_fd(dirfd, fullname, onerror)
File “/home/qiime2/miniconda/envs/qiime2-2019.4/lib/python3.6/”, line 438, in _rmtree_safe_fd
onerror(os.unlink, fullname, sys.exc_info())
File “/home/qiime2/miniconda/envs/qiime2-2019.4/lib/python3.6/”, line 436, in _rmtree_safe_fd
os.unlink(name, dir_fd=topfd)
OSError: [Errno 30] Read-only file system: ‘metadata.yaml’

Hi @drmusk,
Can you double check to make sure there is in fact a paired-end-demux.qza in the directory you are working in, double check the exact name too. This is the most common source of this error, an incorrect file path.

Yes Mehrbod. You are right. Actually I made paired-end-demux.qza in one computer and moved it to other computer for further processing and that might resulted in a change in manifest file oriented paired-end-demux.qza sequences.
When I again started working in first computer it went well.

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