Some of these errors were present before trying to add the 8266.
I'm unsure what to do about this !
I have tried:
turn off virus protection & win firewall
delete packageindex.json (but could not then Update it in tools/board/bopard manager).
I can access the URL for the 8266....json file.
Switching it off and on !!!!!
AND... adding the following lines to "C:\Program Files (x86)\Arduino\arduino.l4j.ini" :
-Djavax.net.ssl.trustStore=NUL
-Djavax.net.ssl.trustStoreType=Windows-ROOT
tried the https bit, same error, plus a lot more and some of my other boards have gone from my list
Error downloading https://arduino.esp8266.com/stable/package_esp8266com_index.json
Error downloading https://downloads.arduino.cc/packages/package_index.json
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at cc.arduino.contributions.packages.ui.ContributedPlatformTableCellJPanel.update(ContributedPlatformTableCellJPanel.java:229)
at cc.arduino.contributions.packages.ui.ContributedPlatformTableCellRenderer.getTableCellRendererComponent(ContributedPlatformTableCellRenderer.java:47)
at javax.swing.JTable.prepareRenderer(JTable.java:5729)
at javax.swing.plaf.basic.BasicTableUI.paintCell(BasicTableUI.java:2114)
at javax.swing.plaf.basic.BasicTableUI.paintCells(BasicTableUI.java:2016)
at javax.swing.plaf.basic.BasicTableUI.paint(BasicTableUI.java:1812)
at javax.swing.plaf.ComponentUI.update(ComponentUI.java:161)
at javax.swing.JComponent.paintComponent(JComponent.java:780)
at javax.swing.JComponent.paint(JComponent.java:1056)
at javax.swing.JComponent.paintChildren(JComponent.java:889)
at javax.swing.JComponent.paint(JComponent.java:1065)
at javax.swing.JViewport.paint(JViewport.java:728)
at javax.swing.JComponent.paintChildren(JComponent.java:889)
at javax.swing.JComponent.paint(JComponent.java:1065)
at javax.swing.JComponent.paintToOffscreen(JComponent.java:5210)
at javax.swing.RepaintManager$PaintManager.paintDoubleBuffered(RepaintManager.java:1579)
at javax.swing.RepaintManager$PaintManager.paint(RepaintManager.java:1502)
at javax.swing.RepaintManager.paint(RepaintManager.java:1272)
at javax.swing.JComponent._paintImmediately(JComponent.java:5158)
at javax.swing.JComponent.paintImmediately(JComponent.java:4969)
at javax.swing.RepaintManager$4.run(RepaintManager.java:831)
at javax.swing.RepaintManager$4.run(RepaintManager.java:814)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:814)
at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:789)
at javax.swing.RepaintManager.prePaintDirtyRegions(RepaintManager.java:738)
at javax.swing.RepaintManager.access$1200(RepaintManager.java:64)
at javax.swing.RepaintManager$ProcessingRunnable.run(RepaintManager.java:1732)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:311)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:758)
at java.awt.EventQueue.access$500(EventQueue.java:97)
at java.awt.EventQueue$3.run(EventQueue.java:709)
at java.awt.EventQueue$3.run(EventQueue.java:703)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:728)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java
ETC ETC...
After closing the IDE and restarting, back to the earlier two line error: