How to install language extension pack 5.1

Hi there,
I downloaded the language extension packs of eng UK, deutsch, and français, but I can’t install them.
I have libreoffice 5.2.4.2 under WINDOWS, and the following extension downloaded: LanguageTool-3.4
When I go to the extension manager, the list of possible extensions shine up, but when I try to activate the German part, it says “Could not create Java implementation loader”. For French, apparently no oxt-file exists, so can’t install that either, and for the English extension, I get the message:(com.sun.star.lang.WrappedTargetRuntimeException) { { { Message = “Bad Zip File, ZipException: Zip END signature not found!”, Context = (com.sun.star.uno.XInterface) @98da3c8 (ImplementationName = “com.sun.star.packages.comp.ZipPackage”) } }, TargetException = (any) { (com.sun.star.uno.Exception) { Message = “Bad Zip File, ZipException: Zip END signature not found!”, Context = (com.sun.star.uno.XInterface) @98da3c8 (ImplementationName = “com.sun.star.packages.comp.ZipPackage”) } } }

Why is all this so difficult?? I never had such problems when using Libreoffice 5.0.6 - all the language packs came with the (custom) installation.

What can I do?

Thanks for your consideration
Dr.G.Muchow

I suppose you mean 5.1.4.2, as there is no fresh 5.2.4.2. For me, all language interfaces were available in the install file, English (UK and US), and Dutch work fine. Maybe you should just run the install file again, select Custom install and select all languages that you want. It also installed a slew of dictionaries for all European languages, and dozens of European and non-European variants of French and Spanish. Maybe the dictionaries that you downloaded were corrupted.