Be sure to open the jacket or email which has product key and find out the
edition of ofice.
1 edition of office would not accept PK of another edition.
Hence if you have a diferent edition installed on the computer, uninstall
all these trial software.
1. now put your PK at microsoft.com/office/backup
2. and click "order now"
3. on next page dont put your adress to order,, scroll down and click
4. type your email address
5. it send an email whcih will have downalod link
6. downalod this office, this is the right edition of office for your PK
which you can install and activate.