I was staring on my phone's Mi logo for like 1/2 hour. I was then trying to get access to my phone's internal storage - tried via fastboot, no luck. Then I booted into TWRP (Volume Up + Power button) and I noticed my PC pop-up showing a usb storage connected. I checked my PC and saw the Mi4c internal storage on my File Explorer. I remembered doing that earlier but it wasn't working then.
I quickly copied the rom from xiaomi.eu into the internal storage and used WTRP to flash it.
I had the same problem and want to share my solution.
1. Boot your phone into TWRP and connect via USB to your PC.
2. On PC - Open "cmd" as admin and change into Minimal ADB and Fastboot directory.
3. Download latest rom file from this forum, rename it to mi4c-rom and copy the zip file into the Minimal ADB and Fastboot directory.
4. type in cmd: adb push mi4c-rom.zip /sdcard/Download
5. In TWRP Menu go to Install and navigate to the Download Folder and select the rom.zip.
6. Clear Delvik Cache and Reboot.