I've been keeping a patient eye out for Forge 1.15 to be released, and just noticed it was listed on the Files page for download, but during installation I get this error every time. I tried the installer on every version listed. I'm unsure if this is an error of mine, or just a result of an early release. Either way, thank you guys for the hard work on it. I'll gladly wait for a stable release if it isn't quite ready yet.
JVM info: Oracle Corporation - 1.8.0_60 - 25.60-b23
java.net.preferIPv4Stack=true
Found java version 1.8.0_60
Added Lets Encrypt root certificates as additional trust
Extracting json
Considering minecraft client jar
Downloading libraries
Considering library net.minecraftforge:forge:1.15-29.0.2
File exists: Checksum validated.
Considering library org.ow2.asm:asm:7.2
Downloading library from https://files.minecraftforge.net/maven/org/ow2/asm/asm/7.2/asm-7.2.jar
java.io.FileNotFoundException: https://files.minecraftforge.net/maven/org/ow2/asm/asm/7.2/asm-7.2.jar
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection$10.run(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection$10.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at sun.net.www.protocol.http.HttpURLConnection.getChainedException(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(Unknown Source)
at net.minecraftforge.installer.DownloadUtils.download(DownloadUtils.java:146)
at net.minecraftforge.installer.DownloadUtils.download(DownloadUtils.java:134)
at net.minecraftforge.installer.DownloadUtils.downloadLibrary(DownloadUtils.java:123)
at net.minecraftforge.installer.actions.Action.downloadLibraries(Action.java:79)
at net.minecraftforge.installer.actions.ClientInstall.run(ClientInstall.java:108)
at net.minecraftforge.installer.InstallerPanel.run(InstallerPanel.java:428)
at net.minecraftforge.installer.SimpleInstaller.launchGui(SimpleInstaller.java:170)
at net.minecraftforge.installer.SimpleInstaller.main(SimpleInstaller.java:143)
Caused by: java.io.FileNotFoundException: https://files.minecraftforge.net/maven/org/ow2/asm/asm/7.2/asm-7.2.jar
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at java.net.HttpURLConnection.getResponseCode(Unknown Source)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getResponseCode(Unknown Source)
at net.minecraftforge.installer.DownloadUtils.getConnection(DownloadUtils.java:203)
at net.minecraftforge.installer.DownloadUtils.download(DownloadUtils.java:144)
... 7 more
Considering library org.ow2.asm:asm-commons:7.2
Downloading library from https://files.minecraftforge.net/maven/org/ow2/asm/asm-commons/7.2/asm-commons-7.2.jar
java.io.FileNotFoundException: https://files.minecraftforge.net/maven/org/ow2/asm/asm-commons/7.2/asm-commons-7.2.jar
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection$10.run(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection$10.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at sun.net.www.protocol.http.HttpURLConnection.getChainedException(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(Unknown Source)
at net.minecraftforge.installer.DownloadUtils.download(DownloadUtils.java:146)
at net.minecraftforge.installer.DownloadUtils.download(DownloadUtils.java:134)
at net.minecraftforge.installer.DownloadUtils.downloadLibrary(DownloadUtils.java:123)
at net.minecraftforge.installer.actions.Action.downloadLibraries(Action.java:79)
at net.minecraftforge.installer.actions.ClientInstall.run(ClientInstall.java:108)
at net.minecraftforge.installer.InstallerPanel.run(InstallerPanel.java:428)
at net.minecraftforge.installer.SimpleInstaller.launchGui(SimpleInstaller.java:170)
at net.minecraftforge.installer.SimpleInstaller.main(SimpleInstaller.java:143)
Caused by: java.io.FileNotFoundException: https://files.minecraftforge.net/maven/org/ow2/asm/asm-commons/7.2/asm-commons-7.2.jar
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at java.net.HttpURLConnection.getResponseCode(Unknown Source)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getResponseCode(Unknown Source)
at net.minecraftforge.installer.DownloadUtils.getConnection(DownloadUtils.java:203)
at net.minecraftforge.installer.DownloadUtils.download(DownloadUtils.java:144)
... 7 more
Considering library org.ow2.asm:asm-tree:7.2
Downloading library from https://files.minecraftforge.net/maven/org/ow2/asm/asm-tree/7.2/asm-tree-7.2.jar
java.io.FileNotFoundException: https://files.minecraftforge.net/maven/org/ow2/asm/asm-tree/7.2/asm-tree-7.2.jar
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection$10.run(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection$10.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at sun.net.www.protocol.http.HttpURLConnection.getChainedException(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(Unknown Source)
at net.minecraftforge.installer.DownloadUtils.download(DownloadUtils.java:146)
at net.minecraftforge.installer.DownloadUtils.download(DownloadUtils.java:134)
at net.minecraftforge.installer.DownloadUtils.downloadLibrary(DownloadUtils.java:123)
at net.minecraftforge.installer.actions.Action.downloadLibraries(Action.java:79)
at net.minecraftforge.installer.actions.ClientInstall.run(ClientInstall.java:108)
at net.minecraftforge.installer.InstallerPanel.run(InstallerPanel.java:428)
at net.minecraftforge.installer.SimpleInstaller.launchGui(SimpleInstaller.java:170)
at net.minecraftforge.installer.SimpleInstaller.main(SimpleInstaller.java:143)
Caused by: java.io.FileNotFoundException: https://files.minecraftforge.net/maven/org/ow2/asm/asm-tree/7.2/asm-tree-7.2.jar
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at java.net.HttpURLConnection.getResponseCode(Unknown Source)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getResponseCode(Unknown Source)
at net.minecraftforge.installer.DownloadUtils.getConnection(DownloadUtils.java:203)
at net.minecraftforge.installer.DownloadUtils.download(DownloadUtils.java:144)
... 7 more
Considering library cpw.mods:modlauncher:5.0.0-milestone.4
File exists: Checksum validated.
Considering library cpw.mods:grossjava9hacks:1.1.0
File exists: Checksum validated.
Considering library net.minecraftforge:accesstransformers:2.0.0-milestone.1-shadowed
File exists: Checksum validated.
Considering library net.minecraftforge:eventbus:2.0.0-milestone.1-service
File exists: Checksum validated.
Considering library net.minecraftforge:forgespi:2.0.0-milestone.1
File exists: Checksum validated.
Considering library net.minecraftforge:coremods:2.0.0-milestone.1
File exists: Checksum validated.
Considering library net.minecraftforge:unsafe:0.2.0
File exists: Checksum validated.
Considering library com.electronwill.night-config:core:3.6.2
Downloading library from https://files.minecraftforge.net/maven/com/electronwill/night-config/core/3.6.2/core-3.6.2.jar
java.io.FileNotFoundException: https://files.minecraftforge.net/maven/com/electronwill/night-config/core/3.6.2/core-3.6.2.jar
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection$10.run(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection$10.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at sun.net.www.protocol.http.HttpURLConnection.getChainedException(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(Unknown Source)
at net.minecraftforge.installer.DownloadUtils.download(DownloadUtils.java:146)
at net.minecraftforge.installer.DownloadUtils.download(DownloadUtils.java:134)
at net.minecraftforge.installer.DownloadUtils.downloadLibrary(DownloadUtils.java:123)
at net.minecraftforge.installer.actions.Action.downloadLibraries(Action.java:79)
at net.minecraftforge.installer.actions.ClientInstall.run(ClientInstall.java:108)
at net.minecraftforge.installer.InstallerPanel.run(InstallerPanel.java:428)
at net.minecraftforge.installer.SimpleInstaller.launchGui(SimpleInstaller.java:170)
at net.minecraftforge.installer.SimpleInstaller.main(SimpleInstaller.java:143)
Caused by: java.io.FileNotFoundException: https://files.minecraftforge.net/maven/com/electronwill/night-config/core/3.6.2/core-3.6.2.jar
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at java.net.HttpURLConnection.getResponseCode(Unknown Source)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getResponseCode(Unknown Source)
at net.minecraftforge.installer.DownloadUtils.getConnection(DownloadUtils.java:203)
at net.minecraftforge.installer.DownloadUtils.download(DownloadUtils.java:144)
... 7 more
Considering library com.electronwill.night-config:toml:3.6.2
Downloading library from https://files.minecraftforge.net/maven/com/electronwill/night-config/toml/3.6.2/toml-3.6.2.jar
java.io.FileNotFoundException: https://files.minecraftforge.net/maven/com/electronwill/night-config/toml/3.6.2/toml-3.6.2.jar
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection$10.run(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection$10.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at sun.net.www.protocol.http.HttpURLConnection.getChainedException(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(Unknown Source)
at net.minecraftforge.installer.DownloadUtils.download(DownloadUtils.java:146)
at net.minecraftforge.installer.DownloadUtils.download(DownloadUtils.java:134)
at net.minecraftforge.installer.DownloadUtils.downloadLibrary(DownloadUtils.java:123)
at net.minecraftforge.installer.actions.Action.downloadLibraries(Action.java:79)
at net.minecraftforge.installer.actions.ClientInstall.run(ClientInstall.java:108)
at net.minecraftforge.installer.InstallerPanel.run(InstallerPanel.java:428)
at net.minecraftforge.installer.SimpleInstaller.launchGui(SimpleInstaller.java:170)
at net.minecraftforge.installer.SimpleInstaller.main(SimpleInstaller.java:143)
Caused by: java.io.FileNotFoundException: https://files.minecraftforge.net/maven/com/electronwill/night-config/toml/3.6.2/toml-3.6.2.jar
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at java.net.HttpURLConnection.getResponseCode(Unknown Source)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getResponseCode(Unknown Source)
at net.minecraftforge.installer.DownloadUtils.getConnection(DownloadUtils.java:203)
at net.minecraftforge.installer.DownloadUtils.download(DownloadUtils.java:144)
... 7 more
Considering library org.jline:jline:3.12.1
File exists: Checksum validated.
Considering library org.apache.maven:maven-artifact:3.6.0
File exists: Checksum validated.
Considering library net.jodah:typetools:0.6.1
Downloading library from https://files.minecraftforge.net/maven/net/jodah/typetools/0.6.1/typetools-0.6.1.jar
java.io.FileNotFoundException: https://files.minecraftforge.net/maven/net/jodah/typetools/0.6.1/typetools-0.6.1.jar
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection$10.run(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection$10.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at sun.net.www.protocol.http.HttpURLConnection.getChainedException(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(Unknown Source)
at net.minecraftforge.installer.DownloadUtils.download(DownloadUtils.java:146)
at net.minecraftforge.installer.DownloadUtils.download(DownloadUtils.java:134)
at net.minecraftforge.installer.DownloadUtils.downloadLibrary(DownloadUtils.java:123)
at net.minecraftforge.installer.actions.Action.downloadLibraries(Action.java:79)
at net.minecraftforge.installer.actions.ClientInstall.run(ClientInstall.java:108)
at net.minecraftforge.installer.InstallerPanel.run(InstallerPanel.java:428)
at net.minecraftforge.installer.SimpleInstaller.launchGui(SimpleInstaller.java:170)
at net.minecraftforge.installer.SimpleInstaller.main(SimpleInstaller.java:143)
Caused by: java.io.FileNotFoundException: https://files.minecraftforge.net/maven/net/jodah/typetools/0.6.1/typetools-0.6.1.jar
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown Source)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at java.net.HttpURLConnection.getResponseCode(Unknown Source)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getResponseCode(Unknown Source)
at net.minecraftforge.installer.DownloadUtils.getConnection(DownloadUtils.java:203)
at net.minecraftforge.installer.DownloadUtils.download(DownloadUtils.java:144)
... 7 more
Considering library java3d:vecmath:1.5.2
File exists: Checksum validated.
Considering library org.apache.logging.log4j:log4j-api:2.11.2
File exists: Checksum validated.
Considering library org.apache.logging.log4j:log4j-core:2.11.2
File exists: Checksum validated.
Considering library net.minecrell:terminalconsoleappender:1.2.0
File exists: Checksum validated.
Considering library net.sf.jopt-simple:jopt-simple:5.0.4
File exists: Checksum validated.
Considering library com.github.jponge:lzma-java:1.3
File exists: Checksum validated.
Considering library com.google.code.findbugs:jsr305:3.0.2
File exists: Checksum validated.
Considering library com.google.code.gson:gson:2.8.0
File exists: Checksum validated.
Considering library com.google.errorprone:error_prone_annotations:2.1.3
File exists: Checksum validated.
Considering library com.google.guava:guava:20.0
File exists: Checksum validated.
Considering library com.google.guava:guava:25.1-jre
File exists: Checksum validated.
Considering library com.google.j2objc:j2objc-annotations:1.1
File exists: Checksum validated.
Considering library com.nothome:javaxdelta:2.0.1
File exists: Checksum validated.
Considering library commons-io:commons-io:2.4
File exists: Checksum validated.
Considering library de.oceanlabs.mcp:mcp_config:1.15-20191212.203412@zip
File exists: Checksum validated.
Considering library net.md-5:SpecialSource:1.8.5
File exists: Checksum validated.
Considering library net.minecraftforge:binarypatcher:1.0.7
File exists: Checksum validated.
Considering library net.minecraftforge:forge:1.15-29.0.2:universal
File exists: Checksum validated.
Considering library net.minecraftforge:installertools:1.1.4
File exists: Checksum validated.
Considering library net.minecraftforge:jarsplitter:1.1.2
File exists: Checksum validated.
Considering library net.sf.jopt-simple:jopt-simple:4.9
File exists: Checksum validated.
Considering library net.sf.jopt-simple:jopt-simple:5.0.4
File exists: Checksum validated.
Considering library net.sf.opencsv:opencsv:2.3
File exists: Checksum validated.
Considering library org.checkerframework:checker-qual:2.0.0
File exists: Checksum validated.
Considering library org.codehaus.mojo:animal-sniffer-annotations:1.14
File exists: Checksum validated.
Considering library org.ow2.asm:asm-analysis:6.1.1
File exists: Checksum validated.
Considering library org.ow2.asm:asm-commons:6.1.1
File exists: Checksum validated.
Considering library org.ow2.asm:asm-tree:6.1.1
File exists: Checksum validated.
Considering library org.ow2.asm:asm:6.1.1
File exists: Checksum validated.
Considering library trove:trove:1.0.2
File exists: Checksum validated.
These libraries failed to download. Try again.
org.ow2.asm:asm:7.2
org.ow2.asm:asm-commons:7.2
org.ow2.asm:asm-tree:7.2
com.electronwill.night-config:core:3.6.2
com.electronwill.night-config:toml:3.6.2
net.jodah:typetools:0.6.1