Something is likely wrong with the fastq input dataset.
Check that it completely loaded. Then click on the bug icon for the dataset to see more of the error message - what you shared is not enough detail to know what is wrong.
- My job ended with an error. What can I do? https://galaxyproject.org/support/tool-error/
- Fastq format troubleshooting is also covered in these first FAQs, including how to reformat certain fastq data retrieved using Download and Extract Reads in FASTA/Q format from NCBI SRA: https://galaxyproject.org/support/#getting-inputs-right
- If the data source was EBI SRA, the datatype needs to be modified due to a known bug, details in this post: https://biostar.usegalaxy.org/p/28718/
If you cannot figure out the issue and are working at Galaxy Main https://usegalaxy.org or can you reproduce the error there, the bug report sent in will report the full error message (you'll get a copy). That will give more information for you to use in troubleshooting and we can also give feedback. Please leave all inputs/outputs undeleted and include a link to this Biostars post in the bug report comments section.
Thanks! Jen, Galaxy team