That doesn't sound good. Which model Aspire V5? What kind of hard drive are you using? What Operating System are you using? Most manufactures offer a diagnostic tool that you can download and use to troubleshoot your hard drive and any time my PC's having problems finding information it's the first thing I use to make sure the drive isn't failing. Here's a link to Speccy, which will display your system details in case you don't know exactly what you have.
Then you should probably run a SFC/Scannow to verify that your OS isn't corrupted or missing some files.
1. Open an Elevated Command Prompt by right clicking the Command Prompt shortcut and choosing Run as Administrator.
2. Type sfc /scannow into Command Prompt and press Enter.
3. SFC (System File Checker) will scan your Windows System files and repair/replace any missing or corrupted OS files.
You could also try resetting your BIOS settings. A lot of people on the ACER site are posting the same problem since January. Most suspect their HDDs are at fault, but a few recommend the following.
Reset BIOS on Acer Laptops:
1. Shut down your computer.
2. Power on the system. As soon as the first logo screen appears, immediately press F2. Sometimes Delete is the key that brings up your BIOS screen.
3. Press F9 and then Enter to load the default configuration.
4. Press F10 and then Enter to save and exit.