It is possible that this question has been asked/answered before. I tried searching through the galaxy-user list archives on nabble but could not find an applicable answer. ----------------------- Bowtie alignments done using a de-multiplexed Illumina sequence data set (CASAVA v.1.8.2) appear to be leading to alignment problem in our local galaxy install. At first glance this appears to be because of the " @SOMETHING<space>READINFO" read names not being handled correctly by bowtie. This is not a galaxy issue per se but what are other users doing to avoid this problem. We are using bowtie v. 0.12.7 (going to upgrade soon) at the moment. Posting a snippet from the alignment file below: MACHINE_NAME:2:1101:1533:1944 1:N:0:CGATGT 4 * 0 0 * * 0 0 NACGAAACGGGTCGGTCCGTCGGCATAGCGCGCCACGGCCTGCGGATCGG #4=DDFFFHHHFHIJHIJIHIIJJJIIIIIJJIHHFFDDDDDDDDDDDDD XM:i:0 MACHINE_NAME:2:1101:2523:1962 16 chr5 80936209 255 50M * 0 0 CTAAAAGGAAAAATTCCAGGGATTAAGGAACTTGAAGTTAGAAAAACTAN IIJJJIHHJJJIHFEIHIJIIJIJJJJIIJIIGJJIJFGHHHFEDAD=4# XA:i:1 MD:Z:49C0 NM:i:1 MACHINE_NAME:2:1101:1596:1971 16 chr13 41692461 255 50M * 0 0 GCTGAATAATAGTCCATTGTGAACATATACCATGTTTTCTTTATTTTTAN JJJJJJJJJIJJIJJJJJJJJJJJJJJHFJJJJJJJJHHHHHFFFFD=4# XA:i:1 MD:Z:49T0 NM:i:1 MACHINE_NAME:2:1101:2670:1962 1:N:0:CGATGT 4 * 0 0 * * 0 0 NTGCACTCGCCTGGATACCGTCGCCGGTGAGGTGGCATTCGAACACACCC --Hemant