Win7 does not know the DVD drive?

Computer Shop News Many users who have installed WIN7 and Windows Server 2008 R2 will find an embarrassing problem: the DVD drive in the computer can't be recognized, and it can't be used normally. This kind of situation mainly appears on the SATA interface DVD drive, and after inquiry, the root of the problem is actually on the WIN7 system, what is going on? Microsoft official explanation This is related to Win7 power management Microsoft officially acknowledged the existence of this problem and explained: This problem is caused by the new power management function of SATA driver (Msahci.sys) Adaptive Link Power Management (ALPM) . Some optical drive ALPM features are enabled and not working properly and may cause the computer to become unrecognizable. However, Microsoft did not provide a patch update for this issue, but suggested that users wait for WIN7 SP1. Is our optical drive only idle at this stage? Simply solve this problem yourself. ■Table: These optical drives may be affected Brand brand remarks model Sony Sony BC-5100S/BC-5600S Pioneer 212CH/217VXL TSST Toshiba/Samsung combined brand TS-L633B DVD+/-RW PLDS Philips/Jianxing merged brand DS-8A3S Modify the power management settings to solve this problem. Explore the problem solving ideas, ALPM is the key ALPM is the built-in adaptive link power management function of WIN7, and some optical drives can not be recognized by WIN7, it is a problem here. So the best solution is to turn off the ALPM built into WIN7 and re-establish a power management plan. To view the existing ALPM, click “start”“all programs”“attachments”“command prompt”, we can see a dialog box, enter “Powercfg/l” I can see several ALPMs that are currently built into the computer. If the user has previously created a power management plan himself, it can be seen here as well. Several ALPMs built into the computer turn off ALPM. In general, we can only choose one of these power plans and cannot turn them off. But now we can disable ALPM here. For example, if we want to turn off the built-in "high performance" power plan of WIN7, enter the following two sets of code: powercfg.exe-setacvalueindex 8c5e7fda-e8bf-4a96-9a85-a6e23a8c635c 0012ee47-9041-4b5d-9b77-535fba8b1442 DAB60367-53FE- 4fbc-825E-521D069D2456 0 Powercfg.exe-setdcvalueindex 8c5e7fda-e8bf-4a96-9a85-a6e23a8c635c 0012ee47-9041-4b5d-9b77-535fba8b1442 DAB60367-53FE-4fbc-825E-521D069D2456 0 Where <8c5e7fda-e8bf-4a96-9a85 -a6e23a8c635c” is the GUID corresponding to the "High Performance" power plan. To turn off the power plan, enter the above code, just replace the GUID corresponding to this power plan. The official solution given by Microsoft Address: Re-establishing a new power plan After the previous operation, several power plans built into WIN7 have been shut down. Now we need to build a new power plan, of course, if you have created it yourself. After the power plan, you can use it directly, no need to do this step. First find the "Power Options" in the "Control Panel" Then click on “Create Power Plan” in the left menu. Enter the name of the new power plan in the "Plan name" box, and then click “Next”. In the “Close Monitor” and “Make the computer go to sleep” box, users can choose according to their needs. Then click “Create” to complete the operation. At this point, the WIN7 system uses the power plan we created ourselves. Originally, the optical drive that ALPM cannot recognize can be used normally. Click “Create Power Plan” to enter the new plan name. Set the parameters of the power plan. At the end: Turning off ALPM is the key to solving the problem. The whole operation process is to close the ALPM that comes with WIN7 and then create a new one. This closing ALPM is cumbersome because it requires a lot of code to be entered, and the subsequent operations are not complicated. Of course, we also hope that WIN7 SP1 can be released as soon as possible and solve this problem tangibly.