I was recently playing on the Pixelmon mod the previous day and it was working just fine, but today I got home and tried to launch Minecraft with nothing different and it repeatedly gave me this same crash report every time:

 

 

Description: Rendering overlay

net.minecraftforge.fml.config.ConfigFileTypeHandler$ConfigLoadingException: Failed loading config file forge-client.toml of type CLIENT for modid forge
    at net.minecraftforge.fml.config.ConfigFileTypeHandler.lambda$reader$1(ConfigFileTypeHandler.java:61) ~[?:?] {re:classloading}
    at net.minecraftforge.fml.config.ConfigFileTypeHandler$$Lambda$5770/1459794929.apply(Unknown Source) ~[?:?] {}
    at net.minecraftforge.fml.config.ConfigTracker.openConfig(ConfigTracker.java:104) ~[?:?] {re:classloading}
    at net.minecraftforge.fml.config.ConfigTracker.lambda$loadConfigs$1(ConfigTracker.java:83) ~[?:?] {re:classloading}
    at net.minecraftforge.fml.config.ConfigTracker$$Lambda$5769/1391126945.accept(Unknown Source) ~[?:?] {}
    at java.lang.Iterable.forEach(Iterable.java:75) ~[?:1.8.0_51] {}
    at java.util.Collections$SynchronizedCollection.forEach(Collections.java:2062) ~[?:1.8.0_51] {}
    at net.minecraftforge.fml.config.ConfigTracker.loadConfigs(ConfigTracker.java:83) ~[?:?] {re:classloading}
    at net.minecraftforge.fml.ModLoader.lambda$null$18(ModLoader.java:208) ~[?:?] {re:classloading}
    at net.minecraftforge.fml.ModLoader$$Lambda$5768/1470373985.run(Unknown Source) ~[?:?] {}
    at net.minecraftforge.fml.DistExecutor.unsafeRunWhenOn(DistExecutor.java:125) ~[?:?] {re:classloading}
    at net.minecraftforge.fml.ModLoader.loadMods(ModLoader.java:208) ~[?:?] {re:classloading}
    at net.minecraftforge.fml.client.ClientModLoader.lambda$startModLoading$7(ClientModLoader.java:132) ~[?:?] {re:classloading,pl:runtimedistcleaner:A}
    at net.minecraftforge.fml.client.ClientModLoader$$Lambda$5762/1417665556.run(Unknown Source) ~[?:?] {}
    at net.minecraftforge.fml.client.ClientModLoader.lambda$createRunnableWithCatch$4(ClientModLoader.java:123) ~[?:?] {re:classloading,pl:runtimedistcleaner:A}
    at net.minecraftforge.fml.client.ClientModLoader$$Lambda$2966/721395199.run(Unknown Source) ~[?:?] {}
    at net.minecraftforge.fml.client.ClientModLoader.startModLoading(ClientModLoader.java:132) ~[?:?] {re:classloading,pl:runtimedistcleaner:A}
    at net.minecraftforge.fml.client.ClientModLoader.lambda$onResourceReload$2(ClientModLoader.java:114) ~[?:?] {re:classloading,pl:runtimedistcleaner:A}
    at net.minecraftforge.fml.client.ClientModLoader$$Lambda$5759/1184138075.run(Unknown Source) ~[?:?] {}
    at net.minecraftforge.fml.client.ClientModLoader.lambda$createRunnableWithCatch$4(ClientModLoader.java:123) ~[?:?] {re:classloading,pl:runtimedistcleaner:A}
    at net.minecraftforge.fml.client.ClientModLoader$$Lambda$2966/721395199.run(Unknown Source) ~[?:?] {}
    at java.util.concurrent.CompletableFuture$AsyncRun.run(CompletableFuture.java:1618) ~[?:1.8.0_51] {}
    at java.util.concurrent.CompletableFuture$AsyncRun.exec(CompletableFuture.java:1610) ~[?:1.8.0_51] {}
    at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289) ~[?:1.8.0_51] {}
    at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1056) ~[?:1.8.0_51] {}
    at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1689) ~[?:1.8.0_51] {}
    at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:157) ~[?:1.8.0_51] {}
Caused by: com.electronwill.nightconfig.core.io.ParsingException: Not enough data available
    at com.electronwill.nightconfig.core.io.ParsingException.notEnoughData(ParsingException.java:22) ~[core-3.6.3.jar:?] {}
    at com.electronwill.nightconfig.core.io.ReaderInput.directReadChar(ReaderInput.java:36) ~[core-3.6.3.jar:?] {}
    at com.electronwill.nightconfig.core.io.AbstractInput.readChar(AbstractInput.java:49) ~[core-3.6.3.jar:?] {}
    at com.electronwill.nightconfig.core.io.AbstractInput.readCharsUntil(AbstractInput.java:123) ~[core-3.6.3.jar:?] {}
    at com.electronwill.nightconfig.toml.TableParser.parseKey(TableParser.java:166) ~[toml-3.6.3.jar:?] {}
    at com.electronwill.nightconfig.toml.TableParser.parseDottedKey(TableParser.java:145) ~[toml-3.6.3.jar:?] {}
    at com.electronwill.nightconfig.toml.TableParser.parseNormal(TableParser.java:55) ~[toml-3.6.3.jar:?] {}
    at com.electronwill.nightconfig.toml.TomlParser.parse(TomlParser.java:44) ~[toml-3.6.3.jar:?] {}
    at com.electronwill.nightconfig.toml.TomlParser.parse(TomlParser.java:37) ~[toml-3.6.3.jar:?] {}
    at com.electronwill.nightconfig.core.io.ConfigParser.parse(ConfigParser.java:113) ~[core-3.6.3.jar:?] {}
    at com.electronwill.nightconfig.core.io.ConfigParser.parse(ConfigParser.java:219) ~[core-3.6.3.jar:?] {}
    at com.electronwill.nightconfig.core.io.ConfigParser.parse(ConfigParser.java:202) ~[core-3.6.3.jar:?] {}
    at com.electronwill.nightconfig.core.file.WriteSyncFileConfig.load(WriteSyncFileConfig.java:73) ~[core-3.6.3.jar:?] {}
    at com.electronwill.nightconfig.core.file.AutosaveCommentedFileConfig.load(AutosaveCommentedFileConfig.java:85) ~[core-3.6.3.jar:?] {}
    at net.minecraftforge.fml.config.ConfigFileTypeHandler.lambda$reader$1(ConfigFileTypeHandler.java:57) ~[?:?] {re:classloading}
    ... 26 more

A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Thread: Render thread
Stacktrace:
    at net.minecraftforge.fml.config.ConfigFileTypeHandler.lambda$reader$1(ConfigFileTypeHandler.java:61) ~[?:?] {re:classloading}
    at net.minecraftforge.fml.config.ConfigFileTypeHandler$$Lambda$5770/1459794929.apply(Unknown Source) ~[?:?] {}
    at net.minecraftforge.fml.config.ConfigTracker.openConfig(ConfigTracker.java:104) ~[?:?] {re:classloading}
    at net.minecraftforge.fml.config.ConfigTracker.lambda$loadConfigs$1(ConfigTracker.java:83) ~[?:?] {re:classloading}
    at net.minecraftforge.fml.config.ConfigTracker$$Lambda$5769/1391126945.accept(Unknown Source) ~[?:?] {}
    at java.lang.Iterable.forEach(Iterable.java:75) ~[?:1.8.0_51] {}
    at java.util.Collections$SynchronizedCollection.forEach(Collections.java:2062) ~[?:1.8.0_51] {}
    at net.minecraftforge.fml.config.ConfigTracker.loadConfigs(ConfigTracker.java:83) ~[?:?] {re:classloading}
    at net.minecraftforge.fml.ModLoader.lambda$null$18(ModLoader.java:208) ~[?:?] {re:classloading}
    at net.minecraftforge.fml.ModLoader$$Lambda$5768/1470373985.run(Unknown Source) ~[?:?] {}
    at net.minecraftforge.fml.DistExecutor.unsafeRunWhenOn(DistExecutor.java:125) ~[?:?] {re:classloading}
    at net.minecraftforge.fml.ModLoader.loadMods(ModLoader.java:208) ~[?:?] {re:classloading}
-- Overlay render details --

In general, we don't provide support for old versions; however, since your issue revolves around a common issue, I see no reason not to provide it. Most likely, your config is either corrupted or formatted incorrectly, so you would just need to go into the `config` folder and remove the erroring config in question.

26 minutes ago, ChampionAsh5357 said:

In general, we don't provide support for old versions; however, since your issue revolves around a common issue, I see no reason not to provide it. Most likely, your config is either corrupted or formatted incorrectly, so you would just need to go into the `config` folder and remove the erroring config in question.

Would I need to delete the actual file itself or the contents of the config because I went to the erroring config and opened it with notepad and there was nothing in the config.

Remove the file. It will only regenerate it with default config if it doesn't exist.