Jan is right
The Portuguese and even the English version for download are incompatible is another language is installed… If the user have a previous instalation of avast! he/she could not update to 4.1.319 using the full setup.exe file.

Two messages of software incompatibility were shonw in my system.
After clincking yes on both, the error message says that the package is broken. This never happens before! It’s a pity! I strongly suggest, if posible, that the user could choose a pair of languages to download

Even when we go to the Control Panel, the software incompatibility error message is shown!