Hi, When loading a mzML file through:

library(MSnbase)
library(mzR)
ms <- openMSfile('path/to/file.mzML')

Trying to access injection time I get in some files the following:

ms$startTimeStamp
[1] "-infinity"

What does it mean? Any workaround? Thanks

I think you are missing some bits of code in your example - it probably should be

ms <- openMSfile('path/to/file.mzML')
info <- runInfo(ms)
ms$startTimeStamp

The reason you read "-infinity" is probably because that's what is encoded in your mzML file. You can check for yourself in R with

grep("startTimeStamp", readLines('path/to/file.mzML'), value = TRUE)

or on the command line with

grep startTimeStamp path/to/file.mzML

In the future, could you please add the output of sessionInfo() to make sure we are talking about the latest version.