Android Question Error while running a project

I get this error in the compile window when I run any of my projects:
B4A Version: 13.10
Parsing code. Error
Error parsing program.
Error description: Syntax error.
Fel uppstod vid linje; 104 (B4XCollections)
Public Sub CreateList (Items As List = Null) As List

And in the Log window:
Objektreferensen har inte angetts till en instans av ett objekt.
Undeclared variable 'items' is used before it was assigned any value.
Undeclared variable 'items' is used before it was assigned any value.
Undeclared variable 'initialized' is used before it was assigned any value.
Undeclared variable 'initialized' is used before it was assigned any value.
Undeclared variable 'initialized' is used before it was assigned any value.
Undeclared variable 'initialized' is used before it was assigned any value.
Undeclared variable 'initialized' is used before it was assigned any value.
Syntax error.

Yesterday it worked, I had B4J installed for a while today but have uninstalled it again.
I have also tested a backup of one of the projects, with the same results.