correct as is QFE 26.66 not valid

[Moxica]

Trying to enter QFE as instructed by ATC, but the value QFE 26.66 can not be entered. (Afghanistan)
Tried 29.66 -went fine.
But then..

Edited March 7 by Moxica

[razo+r]

17 minutes ago, Moxica said:

Trying to enter QFE as instructed by ATC, but the value QFE 26.66 can not be entered. (Afghanistan)
Tried 29.66 -went fine.
But then..

Most modern western aircraft don't use QFE anymore so they don't have the altimeters anymore that have big ranges of pressure settings.

Use the QNH from the briefing instead of the QFE.

[Moxica]

25 minutes ago, razo+r said:

Most modern western aircraft don't use QFE anymore so they don't have the altimeters anymore that have big ranges of pressure settings.

Use the QNH from the briefing instead of the QFE.

Where the heck does one acquire all this info? And remember it! 
I'm impressed, thanks.
But shouldn't it be considered a bug then?
Because it was instructed by ATC upon landing request?
 

Edited March 7 by Moxica

[razo+r]

10 minutes ago, Moxica said:

Where the heck does one acquire all this info? And remember it! 
I'm impressed, thanks.
But shouldn't it be considered a bug then?
Because it was instructed by ATC upon landing request?
 

Well, the ATC system is an ancient relict from Lockon era if not before, where there were mainly russian aircraft around that did use QFE. So in that sense it's not really a bug but more a deprecated and out of date system.

[Moxica]

Thanks again.
I'll mark THAT as solution.