Encoder won't encode or export

Hello,

I'm having trouble exporting .H264 files in Media Encoder. It just sits blank and won't encode anything. The last couple of days, it would encode, but develop a red MEDIA OFFLINE screen for the first 30 seconds of the video, when that would never be the case before. Over the last few days I've encountered several issues wth Media Encoder. Was hoping the latest update would remedy that. May also be an issue with the Dynamic Link server. Any help or advice would be appreciated.