[13:35:23 INFO]: Starting minecraft server version 1.7.10
[13:35:23 INFO]: Loading properties
[13:35:23 WARN]: server.properties does not exist
[13:35:23 INFO]: Generating new properties file
[13:35:23 WARN]: Failed to save server.properties
java.io.FileNotFoundException: server.properties (Acceso denegado)
 at java.io.FileOutputStream.open0(Native Method) ~[?:1.8.0_151]
 at java.io.FileOutputStream.open(Unknown Source) ~[?:1.8.0_151]
 at java.io.FileOutputStream.<init>(Unknown Source) ~[?:1.8.0_151]
 at java.io.FileOutputStream.<init>(Unknown Source) ~[?:1.8.0_151]
 at lq.b(SourceFile:47) [minecraft_server.1.7.10.jar:?]
 at lq.a(SourceFile:41) [minecraft_server.1.7.10.jar:?]
 at lq.<init>(SourceFile:35) [minecraft_server.1.7.10.jar:?]
 at lt.e(SourceFile:97) [minecraft_server.1.7.10.jar:?]
 at net.minecraft.server.MinecraftServer.run(SourceFile:339) [minecraft_server.1.7.10.jar:?]
 at lj.run(SourceFile:628) [minecraft_server.1.7.10.jar:?]
 

Minecraft Forge displays this message periodically. I'm trying to make a Minecraft Forge Server but it displays the same result again and again.

Minecraft version:1.7.10

Forge file name:forge-1.7.10-10.13.4.1614-1.7.10-universal.jar

1.7.10 isnt supported by this forum anymore i believe so your probably going to have to check somewhere else,