I went through the same steps as you did above and finally gave up and opened up a support ticket (#00044911) and the support engineer told me it had something to do with company certificate. The .log file only showed errors when creating the .xls or .csv when retrieving the the SSL certificate.to make the file. The final recommendation was "double check your company SSL certificate settings." I contacted our company Security IS group who made the certificate and they said the certificate has no such settings to exclude those files being generated from an internal server. So basically, SolarWinds says it's our fault, my company says it's SolarWinds' fault. Either way, I'm still not getting .xls or .csv from the scheduler. Only .pdf and .html of which I can export to .xls through the web report "Export to Excel" link. So I'm just doing that for now until I ask to reopen the case.
I'm having a similar issue.
When you hit the export link, does it redirect you back to the "Manage Reports" view?