Some times ago I also had this problem and it was successfully solved by temporarily disable digital signature verification drivers. There are some screenshots in russian language. http://www.windxp.com.ru/win8/article_44.htm
For the first time we need moove the mouse to the right upper corner of win 8.1 and vertical menu will appear.
Next we must choose the "Parameters" or "Options" (paragraf with cogwheel) and then press Win+I. Next with pushing shift choose "Off"("Shutdown") and "Reload" ("Restart").
Next in new menu choose "Diagnostics".
Next "Additional options".
Next "Options of load".
Next choose "Restart".
Next in new menu choose F7 ("Disable mandatory driver signing checks").
Windows will loaded. Switch SH-201.
Next in "Control panel" find "devices and printers", find SH-201 and right click of mouse on them, ckick on properties, in new window on the second insert find batton "Properties", then "Change Options", insert "Driver", button "Update", in new window choose "Search for the drivers on this computer".
Then we must choose the Folder with driver for win 8 "sh201_win8d_v100".
And that's all...
If this driver will not work we may do next procedure:
Do some change in driver file RDIF1065.INF:
1. Type ";" in line ;CatalogFile=RDID1065.CAT
2. And rename to the NTamd64 all "NTamd64.6.2, NTamd64.6.3" in this file.
And again update this driver in the properties of SH-201.