SMTNG wrong on my server(Info Update)

Hi, it's me again.
Problem history:
1) i tryed to connect to server, but message "Failed to login (Invalid session)" appeared everytime.
2) I loaded backup from Aternos. Everything OK. but the backup was too old.
3) I Uploaded my word from my .zip backup. mesage "Failed to login... " appears again.

Please, any suggestions?

I Tryed KeiNet Launcher. I Tryed TeamExtrem Launcher.
I Tryed Login as Jeez, I tryed Login as jeez.
I Tryed Whitelist enabled, I Tryed Whitelist disabled.
I can try, delete whole .minecraft folder, and create it again by launcher.

Now I am uploading world from my disk. (again)
It WILL take a while with my upload speed.
After that I am open for help.

OK. for now it is working again.
I uploaded one of my backup, but not the newest one.
Where was the problem i dont know.

Why i cannot upload file bigger than 50M ?
My actual world in .zip is about 90M.
It was downloaded from aternos, so why i cannot upload it back?

Yess I do.
Your questions means, that my hypothesis was right.
I needet to change online mode to "cracked"
I was not sure till now.
I am sorry for problems guys.
You done a greate piece of work, and inspired me.
Good bless.

PS: what about uploading my backup (94M) ? new thread, or can i get an answer here?

Please explain the problem.
Your answer is like "sun is yellow, moon is white"
Yes for most people is upload slower, but that's user problem.
Or it occures problems on server side? Why?
And nowadays becomes normal to hawe unagregated linear line.
eg. 4Mbit/s up and down without restriction.
So please what do you realy mean by your answer?

If there must be restriction on serverside, then restrict uploading time.

If smbdy uploading 50MB with speed "A" for half an hour.
Then smbdy else can upload "100MB with speed "2xA" in same time and same resources.