In UPM, When the plugin drop down is clicked, it is not showing the options under it.

[arunk]

The plugin gets stuck like shown in above screenshot.

It also shows the following error at the log.

java.lang.IllegalArgumentException: Illegal character in path at index 59: http://myserver.com/tk/rest/plugins/1.0/${atlassian.plugin.key}-key
at java.net.URI.create(URI.java:852)
at javax.ws.rs.core.UriBuilder.fromUri(UriBuilder.java:95)
at com.atlassian.plugins.rest.module.RestDelegatingServletFilter$JerseyOsgiServletContainer.doFilter(RestDelegatingServletFilter.java:171)
at com.sun.jersey.spi.container.servlet.ServletContainer.doFilter(ServletContainer.java:795)
at com.atlassian.plugins.rest.module.RestDelegatingServletFilter.doFilter(RestDelegatingServletFilter.java:73)
... 101 filtered
at com.atlassian.plugins.rest.module.servlet.RestSeraphFilter.doFilter(RestSeraphFilter.java:40)
... 73 filtered
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745 

[Brant Schroeder]

@arunk Here is a KB that will guide you through the steps needed to fix the issue.  

• https://confluence.atlassian.com/confkb/upm-fails-to-load-with-message-illegal-character-in-path-at-index-1014275489.html 
• https://confluence.atlassian.com/confkb/how-to-manually-remove-malfunctioning-add-ons-113705118.html