Backup transaction log

Hi,
I have error when i backup the transaction log of master and msdb database.
I think there is an error because the model of this database is simple.
can i modify the model and write full ?

I have another question,
I have a db with 1 db file of 11Go, i have to create secondary files or not.No, you can't change the Model database.

No, you don't need to add secondary files, but it might be a good idea.

-PatP|||Are you using the enterprise manager?|||Master database doesn't allow Differential or log backups.
Post the error message that u get while backing up the transaction log for msdb.

Howdy!|||From the tool list go to shrink database; File; change shrink to transaction log. before implentation. Go out to network and very the log size. Then go back to EM and shrink log. Again go for verifaction.

Live from Dodge City USA, Washington DC|||Yes i using entreprise manager

the error i get for msdb is the following :

"La sauvegarde ne peut tre effectue sur cette base de donnes. Cette sous-tche est ignore"|||Sorry, I need to see that in English|||viola

"the safeguard cannot be carried out on this basis of data. This sub-task is ignored "

Google...yeah baby...|||Sorry, I need to see that in EnglishTo quote W.C. Fields "Go away kid, ya bother me!"

The nickel translation is something like: "That option can't be used for this database. It will be ignored."

-PatP|||Again, I'm working with lots of data. about 290,000,000 records. In the cleanup process backups of the data is most important. After each batch run I shrink the transaction log. With that amount of data soon the log will be as big as the data file. At least that's what I was running into. Please follow the instruction above.