The JAR files that are required to launch Java® Web Start based designers are now signed with a new certificate. The new certificate is valid until May 23, 2022. The old certificate that was used to sign JAR files shipped in earlier releases, expires on January 1, 2021. After this date, you cannot launch workflow designer, form designer and policy join directive panels.
The expiration of the certificate does not impact end user functions like change password, request access, provisioning accounts, approving requests, and so on.
Read this flash alert article for instructions on how to resolve the issue:
https://www.ibm.com/support/pages/node/6322193------------------------------
Beth Carroll McCawley
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