Unknown device unable to identify

Hello,
Every time I start my PC, Windows detects an unknown device and cannot install or find a driver...
In the device manager, I can't access the ID number of this device (in the details tab, I don't have that line). I can't find any information to identify this device: type, manufacturer, and location unknown! Reinstalling the driver does not work. Provider, date, and version of the driver are unknown too! Updating does not work.
And in the details tab, I don't understand the following information (and this doesn't help me identify this unknown device!)

Device class GUID: {00000000-0000-0000-0000-000000000000}
Physical device object name: \Device\00000044
Capabilities: 00000000
Enumerator: ROOT
Power Data:
Current power state: D3
Power management functions:
00000009
PDCAP_D0_SUPPORTED
PDCAP_D3_SUPPORTED
Power state mappings:
S0 -> D0
S1 -> D3
S2 -> D3
S3 -> D3
S4 -> D3
S5 -> D3
Removal policy (+ default): 00000001
Device path: ROOT\UNKNOWN\0000
Devnode status: 01802401
DN_ROOT_ENUMERATED
DN_HAS_PROBLEM
DN_DISABLEABLE
DN_NT_ENUMERATOR
DN_NT_DRIVER
Problem code: 00000001
Parent: HTREE\ROOT\0
Siblings: Root\*6TO4MP\0000
Root\*ISATAP\0000
Root\*ISATAP\0001
Root\*TUNMP\0000
Root\ACPI_HAL\0000
Root\COMPOSITE_BATTERY\0000
Root\ISCSIPRT\0000
Root\LEGACY_AFD\0000
Root\LEGACY_AMDKMDAG\0000
Root\LEGACY_ATAPI\0000
Root\LEGACY_BEEP\0000
Root\LEGACY_CLFS\0000
Root\LEGACY_CRCDISK\0000
Root\LEGACY_DRIVERHARDWAREV2\0000
Root\LEGACY_DXGKRNL\0000
Root\LEGACY_HTTP\0000
Root\LEGACY_INTELKMD\0000
Root\LEGACY_IPFILTERDRIVER\0000
Root\LEGACY_IRDA\0000
Root\LEGACY_KSECDD\0000
Root\LEGACY_LLTDIO\0000
Root\LEGACY_MFEAVFK\0000
Root\LEGACY_MFEBOPK\0000
Root\LEGACY_MFEHIDK\0000
Root\LEGACY_MFERKDK\0000
Root\LEGACY_MFESMFK\0000
Root\LEGACY_MOUNTMGR\0000
Root\LEGACY_MPFP\0000
Root\LEGACY_MPSDRV\0000
Root\LEGACY_MSISADRV\0000
Root\LEGACY_NATIVEWIFIP\0000
Root\LEGACY_NDIS\0000
Root\LEGACY_NDISUIO\0000
Root\LEGACY_NDPROXY\0000
Root\LEGACY_NETBT\0000
Root\LEGACY_NSIPROXY\0000
Root\LEGACY_NULL\0000
Root\LEGACY_PEAUTH\0000
Root\LEGACY_PSCHED\0000
Root\LEGACY_RASACD\0000
Root\LEGACY_RDPCDD\0000
Root\LEGACY_RDPENCDD\0000
Root\LEGACY_RSPNDR\0000
Root\LEGACY_SECDRV\0000
Root\LEGACY_SMB\0000
Root\LEGACY_SPLDR\0000
Root\LEGACY_TCPIP\0000
Root\LEGACY_TCPIPREG\0000
Root\LEGACY_TDX\0000
Root\LEGACY_VGASAVE\0000
Root\LEGACY_VOLMGRX\0000
Root\LEGACY_VOLSNAP\0000
Root\LEGACY_WANARPV6\0000
Root\LEGACY_WDF01000\0000
Root\MS_L2TPMINIPORT\0000
Root\MS_NDISWANBH\0000
Root\MS_NDISWANIP\0000
Root\MS_NDISWANIPV6\0000
Root\MS_PPPOEMINIPORT\0000
Root\MS_PPTPMINIPORT\0000
Root\MS_SSTPMINIPORT\0000
Root\RDP_KBD\0000
Root\RDP_MOU\0000
Root\SCSIADAPTER\0000
Root\SYSTEM\0000
Root\SYSTEM\0002
Root\UMBUS\0000
Root\volmgr\0000
Installation error: No driver has been selected for the device information set or one of its elements.
E0000203

I want to clarify that my PC is functioning well, I don't notice any abnormalities in its operation...
I recently tried a USB flash drive that Vista never detected (the key blinks, I hear the device detection sound, a symbol appears in the bottom right corner of the taskbar for a few seconds and then poof... nothing) but apart from this small issue, I don't see where it could be coming from... I tested my USB ports with other drives or devices (keyboard and iPhone) and they seem to work.
I am therefore perplexed and don't know what to do...

Can you help me? SOS! Please!

Acer Aspire 5810TG
Windows Vista Home Premium SP2 32 bits

Configuration: Windows Vista / Firefox 3.6.6