When you are registered as a data provider in the ecoEditor you have an access to unlinked undefined UPR datasets of the active database. This database is regularly updated with the new datasets which are regularly submitted by various data providers.
When a new dataset is accepted to the database it quite often contains new master data (e.g. new product, new unit, etc.). This new master data has to be "added" to your version of the ecoEditor. This does not happen automatically. In the ecoEditor you have to go to File -> Update Master Data.
If your master data is not up to date the ecoEditor will keep you from doing many actions (such as searching for dataset in the database, opening dataset from your computer, etc.) and you will receive an error message. Once you have updated your master data you will be able to continue your work in the ecoEditor as usual.