search_primer_pair fails in the clustalo stage

[IdoBar]

I'm trying to get a basic working example, using a single primer pair, with the following command:

i=13
search_primer_pair(name=sep_primers$Primer_name[i],
            clustal_options=c(exec="D:/Bioinformatics/Tools/R_bins/clustal-omega-1.2.2-win64/clustalo.exe"),
                   sep_primers$Primer_seq_fw[i], sep_primers$Primer_seq_rv[i],
                   num_aligns=10, total_primer_specificity_mismatch=3)

But I get the following error:

Error in file(con, "rb") : cannot open the connection
In addition: Warning messages:
1: running command '"D:/Bioinformatics/Tools/R_bins/clustal-omega-1.2.2-win64/clustalo.exe" --infile C:\Users\ibar\AppData\Local\Temp\RtmpqaLDsC\file141c4a4152fb.fas --outfile C:\Users\ibar\AppData\Local\Temp\RtmpqaLDsC\file141cb552430.aln --threads 1' had status 1 
2: In file(con, "rb") :
  cannot open file 'C:\Users\ibar\AppData\Local\Temp\RtmpqaLDsC\file141cb552430.aln': No such file or directory

It seems like the intermediate fasta file (C:\Users\ibar\AppData\Local\Temp\RtmpqaLDsC\file141c4a4152fb.fas) does not exist in that folder.

Any ideas?

I'm using the latest github version, on windows and R3.3.1.

Thanks, Ido