The SUSY Les Houches Accord specifies (arXiv:hep-ph/0311123, section 3):

• The first character of every line is reserved for control and comment statements. Data lines should have the first character empty.
  …
• A line with a blank first character is a data statement, to be interpreted according to what data the current block contains. Comments and/or descriptions added after the data values, e.g. “ ... # comment”, should always be added, to increase readability of the file for human readers.

According to that, each data line (lines within a block) must start with at least one space. However, lines in SLHA files generated by SARAH (using MakeSPheno[]) generally don’t start with spaces (see Package/SPheno/SPhenoLesHouchesAndMake.m). This is causing problems, for example, with pySLHA (arXiv:1305.4194). When pySLHA encounters such lines without initial spaces, it simply removes them from the input entirely. Thus, it would be nice if SARAH’s SLHA files could be made conforming by adding a space before every data line.

To what blocks do you refer exactly? The spectrum file look fine. Or do you mean the Les Houches input files (which I would expect to be read only by SPheno)?

Oh, sorry – I mean the Les Houches input files (LesHouches.in.*). I wanted to use pySLHA to manipulate the input files for SPheno and ran into the issue described above.

ok, here now with spaces.