cant append multiple Diff backups to same file?...

I run two different types of backups on the same database.
A monthly full and nightly diffs appending to the same full file - file 'A'
A weekly full with 10 min trans log backups appending to same file - file
'B'- during working hours.
2 strategies, 2 backup files.
These are new strats that have gone live this week - tuesday in fact. The
monthly and weekly both ran fine on tuesday as did the nightly diff and all
the TS backups througout the day. last night - Weds - the nightly diff failed
with the following error:
"
Executed as user: <USERNAME>. Cannot perform a differential backup for
database "objectstore", because a current database backup does not exist.
Perform a full database backup by reissuing BACKUP DATABASE, omitting the
WITH DIFFERENTIAL option. [SQLSTATE 42000] (Error 3035) BACKUP DATABASE is
terminating abnormally. [SQLSTATE 42000] (Error 3013). The step failed.
"
Whilst the error is perfectly legible I dont understand what its implying -
cant I add multiple Diff backups to the same full backup OR is my weekly / 10
mins on the same database (but to a diff backup file) ballsing things up for
me somehow? If this is the case how come everything ran fine on tuesday night?
Any help gets beers.
THanks
Alastair Jones.
I shoudl add that the chronology of the backups is as follows:
monthly init @. 7am first tues of month to file A
weekly init @. 7.30 Am tuesdays to file B
nightly diff to file A @. 2215 nightly
TL backups to file B every 10 mins
"Methodology" wrote:

> I run two different types of backups on the same database.
> A monthly full and nightly diffs appending to the same full file - file 'A'
> A weekly full with 10 min trans log backups appending to same file - file
> 'B'- during working hours.
> 2 strategies, 2 backup files.
> These are new strats that have gone live this week - tuesday in fact. The
> monthly and weekly both ran fine on tuesday as did the nightly diff and all
> the TS backups througout the day. last night - Weds - the nightly diff failed
> with the following error:
> "
> Executed as user: <USERNAME>. Cannot perform a differential backup for
> database "objectstore", because a current database backup does not exist.
> Perform a full database backup by reissuing BACKUP DATABASE, omitting the
> WITH DIFFERENTIAL option. [SQLSTATE 42000] (Error 3035) BACKUP DATABASE is
> terminating abnormally. [SQLSTATE 42000] (Error 3013). The step failed.
> "
>
> Whilst the error is perfectly legible I dont understand what its implying -
> cant I add multiple Diff backups to the same full backup OR is my weekly / 10
> mins on the same database (but to a diff backup file) ballsing things up for
> me somehow? If this is the case how come everything ran fine on tuesday night?
> Any help gets beers.
> THanks
> Alastair Jones.
>