Forge 1.8.9 could not access forge.jar

[StarCraft]

Hey guys I had some problems with 1.8.9 that some files were missing then i decided to reinstall Minecraft now I tried to Install it with the clean Minecraft again. First I tryed to install it with Java that I downloaded from the Java Website but then if Itry to run it an error message pops up and says that the Files have some errors and it could not install it. So I tried to install it without the external Java I copied the file into the Minecraft Programm Folder and tried to run the Forge file with the Java.exe file from Minecraft. But then it says that it could not acces the Forge installer. I dont know what i could do now pls help me.