The launcher Console said this:
[B#456] SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
[B#456] SLF4J: Defaulting to no-operation (NOP) logger implementation
[B#456] SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
[B#456] Starting download of https://www.dropbox.com/s/ic0nnif50zxe7f1/MangoCraft.zip?dl=1, with 3 tries remaining
[B#456] File version.json not found in C:\Users\djtri\AppData\Roaming\.technic\modpacks\mangocraftpack\bin\modpack.jar
Link to modpack: https://www.dropbox.com/s/ic0nnif50zxe7f1/MangoCraft.zip?dl=1
modpack name: mangocraftpack