but in UmbracoCms.7.5.6 i can use webforms

Yes

why i can't in this version ?

Is it what are you looking for?

No why this version is not working with webforms?

Hopefully you'll understand we don't want to invest time in the new template editor to make it support a technology we don't think people should use any more.

ok but if it work with the same as old version this well be the best ?

but if it's work as it is in old version will be the best way or you can remove this option

Umbraco released new editor for templates, that is not supporting webForms

You can downgrade Umbraco to oldest version

I hope in new version we see this option again

No, webforms is old technology

Adel, rendering engine is still working, doesn't work only editor in backend

How? it's not working overall.

what error do you have ?

Can you show?

Beforesave

after save

also i get mvc templete although i change To switch the default rendering engine to WebForms .

Adel, check please that you merged /config/trees.config correctly?

i'm not making in changes in tree.config

but you have to do changes in this file while upgrading of umbraco

try to replace it with one from Umbraco 7.7

i was try this in version 7.7.0 and 7.7.6 and i get same error but version 7.5.6 is worked well this problem show in version 7.6 and latest versions

i was try this in version 7.7.0 and 7.7.6 and i get same error but version 7.5.6 is worked well this problem show in version 7.6 and latest versions

Adel, did you replace trees.config with file from 7.7?

yes , I do this now and have same problem