20 Most Recent HP ProBook 4540s Notebook PC ENERGY STAR Questions & Answers

push volume up key.?

RTM? yet (if you had, it be NO)https://support.hp.com/us-en/product/hp-probook-4540s-notebook-pc/5229455/manuals

Simply unplug the power from the adapter, leave for some minutes then reconnect.

it might be two reason 1-due to overheating and if u format ur lappy and install other os then probably this prob occur ,this can be undo by right click on my computer icon and check if all the components are working or not if there are small triangles formed then this are not installed and u have to install them through net or recovery is best. 2- the charger id burnt out due to low or high voltages fluctuations.in this situation u have to buy a new charger or repair the old one by arun

Hi,Try using Fn key + the F1-12 buttons.Hope that the issue is that simple, please reply to this: did it or it didn't help.

you can try using the key F. sometimes depend of the adjustment BIOS setup, the key FN can be enable, or dissable. God bless you

Do you mean the locking function on the screen when you close it?

What were you doing ,just prior to the shut down? Take a look at this:http://pcsupport.about.com/od/fixtheproblem/ht/stoperrors.htm

on ONE PC or all and TV? answering for ALL PC fail. your router not told read the manual on our unstated router . then using (a it told you) a browser on the PC go to 192.x.y.z address, (it tells you) and set DNS to 1.1.1.1 save exit router service page. see it works./ the router has a name , 15 makers? and zillions of models all are not the same but all have a DNS page, ever one,(for 20 years)

The only way I know to reset or clear the password is to know the original one. BIOS passwords are stored in Flash memory and therefore cannot be cleared by removing the CMOS battery like in the good old days.

I'm assuming your using Windows 10. Look at the keyboard. On the top row of buttons, just above the numbers, there are a series of 'f' number buttons. Check button f12. It should have a small light on it. White means the wifi is turned on, orange means it is turned off. press the button to switch it on and off. The laptop uses the term "Airplane Mode". If this doesn't work you will need to check your WiFi network is listed on the laptop. Go into 'Settings' and go to the 'Network & Internet' settings. Go to the WiFi settings button listed on the left of the screen. You should see your network listed. If you cannot see it listed go to "see available networks" and click your network. It will ask for your security Code to be able to connect.

It sounds as if your laptop is overheating. You need to service the cooling system by clearing any dust and debris from it and also applying fresh thermal paste.

did you change OS> did change the OS since bought new? no OS stated, why does not one person here say what OS is there.???? its half the system. that. it came new with Linux or windows XP to Windows 8.1 in 32bit and 64bit versions (click control panen, click system) behold the true OS name and version before your eyes. its like saying my FORD died, and no model, gee a Model "A:? here are some facts, most times. dead USB is this. you changed the OS and failed to use the HP driver at HP.com now 1 usb chip works and the other does notl my Elitebook does that, I upgraded to W10 (with zero HP support on purpose) then USB 3 ports went dead, so had to ID the chip its a NEC chip the Intel inside is USB2 only. then the NEC web site had my chip driver. and now those ports work. See how not saying your OS makes help so hard, this is my example. first test the ports only with a test mouse (test all ports now) think small think simple and a mouse is that. does that fail, i can think of 100s of USB devices that will fail hard in w10, all old things why not tell the helper what you plugged in. and be web connected are you.? tell if DM device manager shows any errors at all? did you first use device manager, to see that device fail plugged in? and then right click it and pick update this driver. or did DM shows all USB ports dead.? it just 2 clicks to get there. then it fails, if yes, then MS does not have the driver, we can go to MS right now and prove that. if i get the HARDWARE IDs out of your Device manager page and look in the MS data base i can see if it is supported. case in point old web cams not. old USB wifi dongles not. and more 100s not and 100s yes. that is how it works and goes. now lets got HP.com and look first there, they made it , NOT MS. lets say you said w8.1-64bit OS and i show. https://support.hp.com/us-en/drivers/selfservice/hp-probook-4730s-notebook-pc/5060893 load all the 4 lines of drivers there. there are 3 paths here get the drivers from HP. get them from MS, automatically PnP or manually (ask now manually) get them from the USB chip maker, intel or whomever. if the USB chip really is dead, and the HP driver fails. (I bet not) then get the hardware IDs. tell me that and will fetch them for you easy. its really easy if you know how,and all ways how. if this shows errors , anywhere here, the driver for these chips are wrong.! if you learn how to get the Hardware IDs its 10x more easy.

Disconnect power adapter. Remove the battery hold down power button 10 seconds plug in Power adapter press Power on

Here is a post about how to hack hp password with Windows Password Recovery Tool, you need it. Don't waste time at unnecessary help. http://www.windowspasswordsrecovery.com/hack-hp-computer.htm

In Explorer go to tools, select block pop ups.