After Effects: Video not playing in composition window

[Oona Switch]

did anyone fine a reason for this?

I have some 8-10 shot roto-ed frame by frame and have worked with masks and layers building a scene
not all of the roto-ed shots are invisible
even though files are stilled linked to the actual source files.

for me It started with the file not opening – and being stuck at 78 % or even 99% for a long time — and just not opening.
i found a way to open the file and all the videos are invisible post that.

It has happened twice —
the work around i did is below — but after working for a week — i am again faced with the same issue

to open the file :
I took the project file to another system – without its linked files – and saved in another name
brought it back and opened and relinked all the files back on mine….

To make the videos visible again:
I went to the source files in finder – and made duplicates of them – and relinked these new files — one by one
(no renaming the files did not change the files from being invisible – they needed actually different files, not just file names)

as you can imagine – I have 4 – 5 sequences like this…. for a 2min film
and doing this process many times is very tedious — not to mention the panic that hits my heart everytime the file refuses to open

SO
if anyone might have an answer to where this error is stemming from
I would be happy to save your file that is not opening and send it back to you if you so need.

TIA
OONA

[Rommel Ricafort]

I just wanna share my solution regarding the issue of the “No Preview”. Recently, I had a struggle to find the solution because my AE CC 2018 has no Monitor and it was really a mess not seeing what’s going on with my COMP. Now it’s working fine. I just downloaded the update for my NVIDIA Graphic Card for Windows 10. Basically, I never thought that the solution would be just to update the driver. Because when I checked on the Device Manager, my Graphic Card is working fine until I tried looking for a new update for the NVIDIA GC. Cheers!