If you are unable to update to the latest IGV I will need more information. You can email this information go
igv...@broadinstitute.org if you don't wish to post it here.
Second, could you take a screenshot of the contents of the directory "<user home>/igv/genomes"? Preferably the screenshot will include the sizes of the files in that directory.
Finally, could you attach a copy of the file "hg19.json" in that directory? Also, if there is a file "hg19.genome" in the directory delete it. In fact this might solve the issue.