Fatal error: Exit code 1 () Warning message: 599 very small variances detected, have been offset away from zero Error in fitFDistRobustly(var, df1 = df, covariate = covariate, winsor.tail.p = winsor.tail.p) : Variances are mostly <= 0 Calls: glmQLFit
The error message is not enough to give exact advice, except that the data is too sparse (low count) for the experimental design.
See the tool form help for methods to tune parameters, EdgeR tutorials, Bioconductor support, and related EdgeR documentation, including https://bioconductor.org/packages/release/bioc/html/edgeR.html.
Thanks! Jen, Galaxy team