Hi Andrei,
after a new installation of a 1.8 NopCommerce software ( for testing and evaluation ) I added a second languaage (Dutch_1_80).
After this update, I can't update categories and items.
After deleting the language I added it works fine.
Same results i had saving the xml English file and re-import it as second language.
On-line shop seems to be working fine always.
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