Issue resolved (for me anyway)!
Microsoft support was extremely responsive. Here's what they asked me to try, and Step 3 worked for me. Hope this helps someone!
Enlai
Step 1:- Check in Safe Mode:
Start the computer in safe mode to check if you are able to view the power settings:
By starting the computer in safe made, we can determine whether the cause of the issue is related to a background service or the corrupted files.
To start in safe mode, follow these steps:
1. Remove all floppy disks, CDs, and DVDs from your computer, and then restart your computer.
2. Click Start, click the arrow next to the Lock button, and then click Restart.
3. Press and hold the F8 key as your computer restarts.
Note: You have to press F8 before the Windows logo appears. If the Windows logo appears, you must try to restart your computer. To do this, wait until the Windows logon prompt appears, and then shut down and restart your computer.
4. On the Advanced Boot Options screen, use the arrow keys to select the Safe Mode option, and then press ENTER.
5. Log on to your computer by using a user account that has administrator rights.
After starting the computer in safe mode check:
1. If the problem continues after you start the computer in safe mode, the problem may occur for one or more of the following reasons:
. There is a problem with underpowered or faulty hardware.
. There is a problem with a driver that is installed.
. There is a problem with an operating system component.
If Step 1 does not resolve the issue, please proceed with Step 2.
Step 2: Perform a Clean Boot:
Perform the clean Boot:
If you are using any Non-Microsoft download manager to download the Adobe flash player, we can isolate those Non-Microsoft services or startup and check if we can download.
On performing a clean boot you can check and fix the issues related to the non-Microsoft application or services conflicting:
Note If the computer is connected to a network, network policy settings may prevent you from following these steps. We strongly recommend that you do not use the System Configuration utility to modify the advanced boot options on the computer unless a Microsoft support engineer directs you to do this. Doing this may make the computer unusable.
Log on to the computer by using an account that has administrator rights.
1. Click Start, type msconfig.exe in the Start Search box, and then press ENTER to start the System Configuration Utility.
2. If you are prompted for an administrator password or for confirmation, type your password, or click Continue.
3. On the General tab, click Selective Startup, and then click to clear the Load startup items check box.
4. On the Services tab, click to select the Hide all Microsoft services check box, and then click Disable all.
Note Following this step lets Microsoft services continue to run. These services include Networking, Plug and Play, Event Logging, Error Reporting, and other services. If you disable these services, you may permanently delete all restore points. Do not do this if you want to use the System Restore utility together with existing restore points.
5. Click OK, and then click Restart.
For further reference please follow the link below regarding clean boot:
How to troubleshoot a problem by performing a clean boot in Windows Vista or in Windows 7
How to set your computer back, to boot normal:-
1. Click on Start.
2. In the Start Search box. Type msconfig and then press ENTER.
3. If you are prompted for an administrator password or for a confirmation, type the password, or click Yes.
4. Click the General tab.
5. Click Normal Startup - load all device drivers and services, and then click OK.
6. When you are prompted, click Restart to restart the computer.
If Step 2 does not resolve the issue, please proceed with Step 3.
Step 3:- Reinstall Power Management settings
1. Click on Start.
2. Type Device Manager in the Start Search box.
3. Click on Device Manager.
4. Click the expand sign next to System Devices.
5. Right-click on the ACPI Fixed Feature Button and select Uninstall. In the "Confirm Device Uninstall" dialog box, click on OK.
6. Restart the system.
7. On restarting the system, Windows will automatically detect and install Power Management on the computer
If Step 3 does not resolve the issue, please proceed with Step 4.
Step 4:- Using the PowerCfg Utility:
1. From an elevated command prompt, use the PowerCfg - tool to change the power policy:
Click Start, click All Programs, click Accessories, right-click Command Prompt, and select Run as Administrator. If you receive a notification from User Account Control simply click Continue.
2. To use the PowerCfg utility, you'll need to open an Administrator Command Prompt. At the prompt, type the command
powercfg -energy
3. After you press [Enter], the PowerCfg utility will begin analyzing your system's power-option settings. After a minute or so, you'll see a report brief and will be prompted to open the report titled energy_report.html for more details.
4. You can type energy-report.html at the prompt to launch Internet Explorer and open the HTML report file.
5. When the report opens, you'll see a header with basic system information followed by color-coded sections that indicate the severity of the problems that were detected. Pink indicates errors, yellow indicates warnings, and white indicates general information. You can use this report to make adjustments to your power-plan settings.
If Step 4 does not resolve the issue, please proceed with Step 5.
Step 5:- System Restore:
System Restore uses restore points to return your system files and settings to an earlier point in time, without affecting personal files.
1. Click Start, type system restore in the Start Search box, and then click System Restore under the Programs section. If you are prompted for an administrator password or for a confirmation, type the password, or click Continue.
2. On the System Restore page, click next.
3. Select a restore point at which you know that the operating system was working, and then click next. The restore point should be a date before the first time that you experienced the problem that is described in the "Symptoms" section. To select a date, use the Choose a different restore point option, and then click next.
4. If you are prompted to specify the disk to restore, select the hard disk on which the operating system is installed and then click next.
5. On the Confirm your restore point page, click Finish.
6. When the restoration process is complete, click Restart.
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