Hi, I encounter the problem that mira doesnt seem to recognize my solexa reads as paired end. (denovo assembly) I have two files (which i merged together into one, since it looks like mira just accepts ONE input file even though being paired-end data) with the folowing format: > head myData_in.solexa.fastq @HWI-H155:68:81MMAABXX:1:1101:1351:2105 1:N:0:GCCAAT TAAGCGAGCAAAATAGTGTCAGAGGTCAGGAGAGAAGGAAACTCACCTCTTGGCTGGAATCTCAATCTTATAAATCACTTCCTCAGAACCAGCGGCCTCTT + @@CDFDBDHHHFH<FF<E3CFE<FF?EBGGGGGI<FHHIGBFBGHII).)1/...5;=A@GCHAEHEC ;;77;?########################### @HWI-H155:68:81MMAABXX:1:1101:1493:2111 2:N:0:GCCAAT AAAGCAAAACTTGAGCTGCGAGCATTCCTTGAACCTTTGCATCCACGACTTTGAGGAAGAGGAACGAAGCTGCTGTGCGTAAGAGCCGTGGCGAAAATTGT + ??;D+AADHHF4A?:A<EGE@E:?E4CFABGGGDC;F*?B*9?*?3?D'-;7B;;7@C6 =A######################################## here the read pairs are denoted by the "1" and "2" before ":N:0:GCCAAT" I know that the previous version was with "/1" and "/2". Can this be the problem? Do i have to change all @headers now?? details: http://en.wikipedia.org/wiki/FASTQ_format#Illumina_sequence_identifiers Thanks, Nicolas