Arrows won't open layer properties

[Sixtyne]

Hello,
for some reason, I can't open the layer properties when I'm clicking on the arrows next to the layer's name.
I'm using the shortcuts to open properties by properties but I can't manage to open all of the properties, or to open an effect property to edit it on the timeline. 
I've been trying to solve this for a day ! Anyone ever encountered this issue ?

[Mylenium]

Right-click on the timeline column headers to expose the "A/V properties" This column also contains the numeric value readouts for properties.

Mylenium

[Ali Jaber]

I don't know how to solve that problem but have you tried pressing function keys (alt, shift, ctrl) while pressing on the arrow?

You can also try to reset the preferences and see if it works for you.

If this didn't work, you may find some shortcuts to be useful: u: show animated properties, uu: show modified properties. Also pressing alt+ any property in the effect controls will add a key for that property, then you can reveal it in the timeline by pressing u.

Besides that, you can right-click on any property of an effect in the effect controls panel and choose "reveal in timeline" then, all the properties of that effect will be shown in the timeline

[Sixtyne]

Thank you for the tips and shortcuts, it helps me to work when this is happening.

Besides everything I tried (what's has been said in the previous answers, re-installing AE, resetting preferences etc...)

i still encounter this, the only fix I found is to restart my computer. And then this bug disappears at least for while.