Can't play after launching app

Failed to download file. cs_cz.lang
Name: cs_cz.lang
URL: http://resources.download.minecraft.net/54/549a0701b4db03659fb974f7676e95e6bf46102b
Error details: Request error -101: ERR_CONNECTION_RESET
Filename on disk: 809b-db57-5f34-970f
Path: C:\Users\jakob\AppData\Local\Temp\809b-db57-5f34-970f
Exists: file