# How to determine whether custom primers were selected on the iSeq 100 once the run is completed?

A section in the RunParameters.xml file titled "\<Planned\_Custom\_Primer>" contains a line for each of the reads indicating **whether or not** custom primers were selected.

The RunParameters.xml file can be found in either the designated output location or the iSeq 100 Temp folder (D:\Illumina\iSeq Runs\[Runfolder]).

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