Hello.

1. Use Windows System Restore to try to return the laptop to the configuration it had yesterday.

2. Re-install the audio driver.

3. If still having problems, revert the laptop to the operating system in which the audio worked correctly. A problem with Win10 is that it is constantly messing with a computer's configuration, but audio is finicky and cannot take much messing with before it stops working correctly.

I have a Inspiron 15 7000 Series 7559 that suddenly stopped recognizing sound devices. The only exception being a small bluetooth speaker. I have reloaded driver twice but it simply will not recognize headphones or speakers. 

I have reloaded driver twice but it simply will not recognize headphones or speakers.

Hello.

1. The recent Windows 10 update might have affected the audio. Use Windows System Restore to try to return the laptop to the configuration it had before the audio stopped working.

2. Another reason that the integrated audio fails to be detected is because the hardware has failed. To check for that, revert the laptop back to the original factory configuration. Test the audio immediately afterward (i.e., before getting on the internet where Windows update will change the configuration again). If the audio does not work at that point, it has failed.

I did the restore but to no avail. I did find from just generally looking around is that there is no "Realtek High Definition Audio Device" listed in the device manager. I have downloaded the Realtek driver several times but nothing. Still no device except a small bluetooth speaker. It works fine but no speakers[even the built in speakers] or headphones are recognized.

Now that I have said all of that: I will gladly Reset to factory settings but I need to know how to save the many non-Windows applications i have.

Desperately awaiting your advice.

Thanks.

how to save the many non-Windows applications i have

I don't know of a painless way to perform a system recovery. It's  not something I do except when I have plenty of free time to deal with it.

I have a backup usb hard drive where I keep an original configuration backup, a duplicate of all my files, etc. I have a text list of all of the programs I will want to install after the recovery, in order of importance. I have folders with copies of the exe's of some of the programs, so I can just click them to reinstall. I have instructions for myself on how to deal with other programs, such as using an installation cd, or downloading from a particular website, installation keys. I have copies of the device drivers, etc.

I have windows 7 and I get the exe's by browsing to the c drive and scrolling down to "Program Files" and "Program Files (x86)". For example, if I expand Program Files and click on the Audacity folder, I can copy "audacity.exe" and paste it in my backup hard drive or a flash drive. However some programs are quite complex to install and I rely on the installation disks that came with the programs. I have made duplicates of the disks of the more expensive programs.

Here are Dell's instructions for re-setting Windows 10. To perform a system recovery, follow the instructions for Factory Image Restore (the 4th & 5th set of instructions).

The 2nd set of instructions would save your data, but you would still lose your installed programs, and it would not be as good a test as using the Factory Image. If the audio originally worked, then it will work again after the Factory Image unless the hardware has failed.

Okay I have done a full reset before and fortunately I am retired so this is really something to do. The only drawback is backing up everything. I have been backing stuff up on a little 1TB Transcend hard drive that I have bought for just that reason. Thanks for your help. 

You're welcome.