I gave a friend a copy of Office 2016 Pro Plus iso for the bulgarian language which matches MSOFTs SHA1 checksum. However, upon install onto a Bulgarian window 10 Pro system after the Pro Plus English was fully removed and other tools used to look for the remaining items that weren't installed, they told me word and excel aren't fully translated to Bulgarian. Is this the case that a language install of a given language still has some items in English but not in that language? I can understand if some words don't translate or that technical words are in English only. Will installing the English version of Office 2016 Pro Plus and then installing the Bulgarian MUI translate better? Moreover, a while back Windows 10 pro was installed in English and the Bulgarian MUI installed, not everything was in the Bulgarian language, particularily the bootup Welcome message and error messages in English. However, when Win 10 was installed that was for bulgarian and not English I was told that everything was in Bulgarian including the Welcome message. But on the other hand, the native speaking Bulgarian said they preferred the English version since there were some things in Bulgarian that were to technically written for a simple English use of the same item. The same was said by a chinese friend who preferred English since when reading the chinese he didn't know what they were trying to say - to techincal - and they are technical (software programmer) and the bulgarian is a linguist in 3 languages. Since there is no Bulgarian VISIO or Project, will installing the English version on a Bulgarian Win 10 which has the Bulgarian office 2016 installed work if the MUI exists in Bulgarian for Visio/Project? We didn't get to the bulgarian vs english proofing tools to see what issues these tools have yet. Is this true for other languages too? I'd think MSoft would hire native speakers to develop the various software products for a given language which would be fully translated and written in easy terms that are understandable.