New installation of JCOP Tools gives class file format error

[markpotts123]

I have a new installation of JCOP Tools which gives "unsupported class file format of version 66.0" error for a basic template applet. This is listed as a known issue in JCOP Tools Getting started app note "If both Eclipse and Java are not same (32 or 64), Following error will be displayed in problem view of Eclipse " however everything is 64-bit.

Java version 22.0.1 (24-04-16)
JDK version 22
Eclipse version 4.32.0 (2024-06)
JCOP Tools version 6.9.0.12

Any suggestions much appreciated.

[markpotts123 · Accepted solution]

I was eventually able to resolve this issue, which turned out to be incorrect installation instructions. When installing under Windows the documentation says install Visual C++ Redistributable 2012. This is to ensure critical Windows libraries (DLLs) that the package depends on are present. One of the library dependencies is MFC100.DLL.

However Visual C++ Redistributable 2012 actually installs MFC110.DLL causing a missing library dependency. Installing Visual C++ Redistributable 2010 installs the required MFC100.DLL and JCOP Tools then runs correctly. Hope this is useful to someone else ;-).