Why can't I access my files, and why can't I see my status bar?

[Ertas10]

Basically, I can't access any files on my Samsung Galaxy Ace plus (GT-S7500), and everytime I try to do so it says "No SD card inserted", even if I try to insert an SD card.
At the same time, my status bar completely disappeared, leaving me with no easy way to know if I have low or high charge.
I also am not able to download anything, either through the Play Store or through my internet browser.
Here are some photos to help you visually understand what's going on.

 

[B. Diddy]

Welcome to Android Central! Try booting into Recovery Mode and wiping the cache partition, which won't erase any personal data. Follow the steps in this video, but instead of selecting Wipe Data/Factory Reset, make sure you select Wipe Cache Partition. When complete, then select Reboot System Now.

https://www.youtube.com/watch?v=FIQElrH_pU8

(I'm guessing that the steps for the Ace 2 will work for the Ace Plus).