Internal error. Please refer to https://jb.gg/ide/critical-startup-errors

com.intellij.ide.plugins.StartupAbortedException: UI initialization failed
    at com.intellij.idea.StartupUtil.lambda$start$15(StartupUtil.java:265)
    at java.base/java.util.concurrent.CompletableFuture.uniExceptionally(CompletableFuture.java:986)
    at java.base/java.util.concurrent.CompletableFuture$UniExceptionally.tryFire(CompletableFuture.java:970)
    at java.base/java.util.concurrent.CompletableFuture.postComplete(CompletableFuture.java:506)
    at java.base/java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1705)
    at java.base/java.util.concurrent.CompletableFuture$AsyncSupply.exec(CompletableFuture.java:1692)
    at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:290)
    at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1020)
    at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1656)
    at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1594)
    at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:183)
Caused by: java.util.concurrent.CompletionException: java.lang.StackOverflowError
    at java.base/java.util.concurrent.CompletableFuture.encodeThrowable(CompletableFuture.java:314)
    at java.base/java.util.concurrent.CompletableFuture.completeThrowable(CompletableFuture.java:319)
    at java.base/java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1702)
    ... 6 more
Caused by: java.lang.StackOverflowError
    at java.base/java.security.AccessController.doPrivileged(Native Method)
    at java.prefs/java.util.prefs.AbstractPreferences.isUserNode(AbstractPreferences.java:1067)
    at java.prefs/java.util.prefs.WindowsPreferences.rootNativeHandle(WindowsPreferences.java:1119)
    at java.prefs/java.util.prefs.WindowsPreferences.<init>(WindowsPreferences.java:461)
    at java.prefs/java.util.prefs.WindowsPreferences.getUserRoot(WindowsPreferences.java:102)
    at java.prefs/java.util.prefs.WindowsPreferencesFactory.userRoot(WindowsPreferencesFactory.java:42)
    at java.prefs/java.util.prefs.Preferences.userRoot(Preferences.java:457)
    at java.prefs/java.util.prefs.AbstractPreferences$1.run(AbstractPreferences.java:1070)
    at java.prefs/java.util.prefs.AbstractPreferences$1.run(AbstractPreferences.java:1068)
    at java.base/java.security.AccessController.doPrivileged(Native Method)
    at java.prefs/java.util.prefs.AbstractPreferences.isUserNode(AbstractPreferences.java:1067)
    at java.prefs/java.util.prefs.WindowsPreferences.rootNativeHandle(WindowsPreferences.java:1119)
    at java.prefs/java.util.prefs.WindowsPreferences.<init>(WindowsPreferences.java:461)
    at java.prefs/java.util.prefs.WindowsPreferences.getUserRoot(WindowsPreferences.java:102)
    at java.prefs/java.util.prefs.WindowsPreferencesFactory.userRoot(WindowsPreferencesFactory.java:42)
    at java.prefs/java.util.prefs.Preferences.userRoot(Preferences.java:457)
    at java.prefs/java.util.prefs.AbstractPreferences$1.run(AbstractPreferences.java:1070)
    at java.prefs/java.util.prefs.AbstractPreferences$1.run(AbstractPreferences.java:1068)
    at java.base/java.security.AccessController.doPrivileged(Native Method)

Коя версия си инсталирал? Ако е 2020.3 или нагоре има вероятност да е заради това, поне така предполагам. Търсих из интернет и видях, че много хора са имали подобен на твоя проблем. Пробвай, ако искаш, да инсталираш по-стара версия, да речем 2020.2.4 (или надолу, както прецениш) и виж дали ще имаш същия проблем. Тук има различни версии:

https://www.jetbrains.com/idea/download/other.html

Благодаря за съвета, но го оправих. Проблемът беше с последният ъпдейт на Windows 10 pro.