I use SQL SMS (SSMS) to perform all actions to my only one MS SQL DB.
I'm only one administrator.
I've never restore a backup.
When I do a full backup everything works.
Afterwards, if I want to make a differential backup next day, I get an error where it cannot find backup:
> Unable to perform a differential backup of the "PMI" database because there is no backup of the current database.
Sorry, I don't provide any more information. All errors appears in French (system language).
I don't have problem if I do differential backups just after the full backup.
This SQL request:
```
SELECT
msdb.dbo.backupset.database_name,
msdb.dbo.backupset.backup_start_date,
msdb.dbo.backupset.backup_finish_date,
msdb.dbo.backupset.expiration_date,
msdb..backupset.type,
CASE msdb..backupset.type
WHEN 'D' THEN 'Full'
WHEN 'I' THEN 'Diff'
WHEN 'L' THEN 'Log'
END AS backup_type,
CASE msdb.dbo.backupmediafamily.device_type
WHEN 2 THEN 'Disk'
WHEN 5 THEN 'Tape'
WHEN 7 THEN 'Virtual Device'
WHEN 9 THEN 'Azure Storage'
WHEN 105 THEN 'A permanent backup device'
ELSE 'Unknown'
END AS device_type_desc,
msdb.dbo.backupmediafamily.physical_device_name,
msdb.dbo.backupset.is_copy_only,
msdb.dbo.backupset.is_snapshot,
msdb.dbo.backupset.first_lsn,
msdb.dbo.backupset.last_lsn,
msdb.dbo.backupset.database_backup_lsn,
msdb.dbo.backupset.checkpoint_lsn,
msdb.dbo.backupset.differential_base_lsn,
msdb.dbo.backupset.fork_point_lsn,
msdb.dbo.backupmediaset.name,
msdb.dbo.backupmediaset.software_name,
msdb.dbo.backupset.user_name,
'EOR'
FROM msdb.dbo.backupmediafamily
INNER JOIN msdb.dbo.backupset
ON msdb.dbo.backupmediafamily.media_set_id = msdb.dbo.backupset.media_set_id
INNER JOIN msdb.dbo.backupmediaset
on msdb.dbo.backupmediaset.media_set_id = backupmediafamily.media_set_id
WHERE 1 = 1
AND (CONVERT(datetime, msdb.dbo.backupset.backup_start_date, 102) >= GETDATE() - 7)
AND database_name IN ('PMI')
ORDER BY --2,
2 desc,3 desc;
```
Return result:
```
database_name backup_start_date backup_finish_date expiration_date type backup_type device_type_desc physical_device_name is_copy_only is_snapshot first_lsn last_lsn database_backup_lsn checkpoint_lsn differential_base_lsn fork_point_lsn name software_name user_name
-------------- ----------------------- ----------------------- ----------------------- ---- ----------- ------------------------- ------------------------------------------------------------- ------------ ----------- ---------------------- ---------------------- ---------------------- ---------------------- ---------------------- --------------- ----- --------------------- --------------------
PMI 2024-11-19 20:25:21.000 2024-11-19 20:25:33.000 2024-12-04 20:25:21.690 D Full Disk D:\SQL Backup\PMI\PMI_backup_2024_11_19_202521_6517704.bak 0 0 104302000000558300001 104302000000558600001 104222000001229700037 104302000000558300001 NULL NULL NULL Microsoft SQL Server sa
PMI 2024-11-19 01:59:51.000 2024-11-19 01:59:53.000 2024-11-27 01:59:51.703 D Full Virtual Device {960E26B9-BCB7-482C-BDAC-207548B83077}3 0 1 104222000001229700037 104222000001231400001 104222000001228000001 104222000001229700037 NULL NULL NULL Microsoft SQL Server AUTORITE NT\Système
PMI 2024-11-19 00:59:26.000 2024-11-19 00:59:37.000 2024-12-04 00:59:26.060 D Full Disk D:\SQL Backup\PMI\PMI_backup_2024_11_19_005925_9360289.bak 0 0 104222000001228000001 104222000001228300001 104219000001378500037 104222000001228000001 NULL NULL NULL Microsoft SQL Server sa
PMI 2024-11-18 01:59:47.000 2024-11-18 01:59:49.000 2024-11-26 01:59:46.977 D Full Virtual Device {230EA0F3-9D31-4279-A5DB-D1E74A9F800D}3 0 1 104219000001378500037 104219000001380200001 104219000001374100001 104219000001378500037 NULL NULL NULL Microsoft SQL Server AUTORITE NT\Système
PMI 2024-11-17 23:00:05.000 2024-11-17 23:00:05.000 2024-11-25 23:00:05.213 I Diff Disk D:\SQL Backup\PMI\PMI_backup_2024_11_17_230005_0981356.diff 0 0 104219000001377400001 104219000001377700001 104219000001374100001 104219000001377400001 104219000001374100001 NULL NULL Microsoft SQL Server sa
PMI 2024-11-17 22:00:07.000 2024-11-17 22:00:19.000 2024-11-25 22:00:07.307 D Full Disk D:\SQL Backup\PMI\PMI_backup_2024_11_17_220007_1834384.bak 0 0 104219000001374100001 104219000001374400001 104219000001366900037 104219000001374100001 NULL NULL NULL Microsoft SQL Server sa
PMI 2024-11-17 09:59:50.000 2024-11-17 09:59:53.000 2024-11-25 09:59:50.867 D Full Virtual Device {04A6F783-F33B-4558-8DCE-53D7FEB0CAEC}3 0 1 104219000001366900037 104219000001368600001 104219000001362500037 104219000001366900037 NULL NULL NULL Microsoft SQL Server AUTORITE NT\Système
PMI 2024-11-17 01:59:54.000 2024-11-17 01:59:56.000 2024-11-25 01:59:54.717 D Full Virtual Device {13E16352-8EC7-48B9-9FEF-B4C486907099}3 0 1 104219000001362500037 104219000001364200001 104219000001355000001 104219000001362500037 NULL NULL NULL Microsoft SQL Server AUTORITE NT\Système
PMI 2024-11-16 23:00:05.000 2024-11-16 23:00:06.000 2024-11-24 23:00:05.683 I Diff Disk D:\SQL Backup\PMI\PMI_backup_2024_11_16_230005_5608786.diff 0 0 104219000001361400001 104219000001361700001 104219000001355000001 104219000001361400001 104219000001355000001 NULL NULL Microsoft SQL Server sa
PMI 2024-11-16 15:45:35.000 2024-11-16 15:45:35.000 2024-11-24 15:45:35.063 I Diff Disk D:\SQL Backup\PMI\PMI_backup_2024_11_16_154535_0369182.diff 0 0 104219000001359000001 104219000001359300001 104219000001355000001 104219000001359000001 104219000001355000001 NULL NULL Microsoft SQL Server sa
PMI 2024-11-16 15:45:21.000 2024-11-16 15:45:22.000 2024-11-24 15:45:21.850 I Diff Disk D:\SQL Backup\PMI\PMI_backup_2024_11_16_154521_8283665.diff 0 0 104219000001358100001 104219000001358400001 104219000001355000001 104219000001358100001 104219000001355000001 NULL NULL Microsoft SQL Server sa
PMI 2024-11-16 15:44:55.000 2024-11-16 15:45:06.000 2024-11-24 15:44:55.180 D Full Disk D:\SQL Backup\PMI\PMI_backup_2024_11_16_154455_1502171.bak 0 0 104219000001355000001 104219000001355300001 104219000001346600001 104219000001355000001 NULL NULL NULL Microsoft SQL Server sa
PMI 2024-11-16 15:41:46.000 2024-11-16 15:41:58.000 2024-11-24 15:41:46.560 D Full Disk D:\SQL Backup\PMI\PMI_backup_2024_11_16_154146_5409243.bak 0 0 104219000001346600001 104219000001346900001 104219000001325800261 104219000001346600001 NULL NULL NULL Microsoft SQL Server sa
PMI 2024-11-16 01:59:50.000 2024-11-16 01:59:53.000 2024-11-24 01:59:50.890 D Full Virtual Device {404A5262-328C-46C9-B456-31D0B249A06D}3 0 1 104219000001325800261 104219000001336600001 104213000001527500272 104219000001325800261 NULL NULL NULL Microsoft SQL Server AUTORITE NT\Système
PMI 2024-11-15 01:59:56.000 2024-11-15 01:59:58.000 2024-11-23 01:59:56.130 D Full Virtual Device {B685428C-A7AE-4642-A17B-CC729BD16D77}3 0 1 104213000001527500272 104213000001538700001 104203000000360300144 104213000001527500272 NULL NULL NULL Microsoft SQL Server AUTORITE NT\Système
PMI 2024-11-14 01:59:52.000 2024-11-14 01:59:55.000 2024-11-22 01:59:52.267 D Full Virtual Device {BE641173-DEA0-400A-A31B-2658897D80B9}3 0 1 104203000000360300144 104203000000366400001 104129000000461200270 104203000000360300144 NULL NULL NULL Microsoft SQL Server AUTORITE NT\Système
PMI 2024-11-13 02:00:05.000 2024-11-13 02:00:08.000 2024-11-21 02:00:04.993 D Full Virtual Device {B7FE8CE1-83D0-4384-BBBC-B729A957527D}3 0 1 104129000000461200270 104129000000472300001 104122000002730300037 104129000000461200270 NULL NULL NULL Microsoft SQL Server AUTORITE NT\Système
```
I can see a task at 02:00:00... I think is `syspolicy_purge_history` default SQL system task.
**UPDATE :** I've disable this task, same issue.
Do you have an idea?