Scan for Unknown Fields' in the "Species Information" window of ARB.
quick phylogenetic classification of your sequences.
background section.To merge ARB files generated by the aligner on the
beta.arb-silva.de page with the SSU or LSU ARB databases you have to convert the field "align_quality_slv" from f0 (float) to i0 (integer).
To do so, open the database with your aligned files in ARB, toggle to expert mode (ARB_NT -> Properties) to access the "Convert fields …" option in the SPECIES INFORMATION window (-> FIELDS -> Convert fields).
Users from non-academic/commercial environments should have a look at the
SILVA License Information