KVM Switch Not Working!?

[cooldowg]

Hello. I bought a KVM switch a few weeks ago to switch between my two computers. It worked fine and loved it. I moved my computers around and when I plugged everything back in...It no longer is working. My keyboard and mouse work fine, but when I go to hit scroll lock twice...nothing happens. Both computers are on.

Can anyone help!?!?!?!?

 

[dextermat]

Hi,

Isn't it scroll lock twice + 1 or 2.

Does anything show up on the screen ?

 

[noidea_77]

What about connecting the computers directly to the screen / keyboard first to see if the are running?

 

[dbhosttexas]

How about some more info such as make / model and configuration? For example I currently have a TrendNET TK803R 8 port KVM using USB KVM cables. This KVM requires usage of the wall wart transformer. This replaced an old Belkin OmniView 4 port PS/2 KVM that used PS/2 KVM cables and ps/2 to usb adapters and did not require power from a transformer.

Some things to check...

#1. If it's PS2. Did you verify you got the keyboard to keyboard ends right on the cables, PCs, and KVM? A flipped keyboard / mouse cable assignment on PS2 will stop everything cold.
#2. If the KVM requires separate power instead of being powered through the device cable (typically leeching off of the monitor), do you have power?
#3. Have you tested the monitor, keyboard, and mouse against the computers to verify they all work?
#4. How many ports / cables do you have? Have you reduced this to a minimum and moved cables around to verify you don't have dead cables?

If everything else checks out, suspect a dead KVM. It happens. If it's new, RMA that sucker and get a new one.

 

[cooldowg]

Dextermat, for me it worked with just scroll lock twice. dbhosttexas, It is an iogear that i bought just a few weeks ago, don't know the exact model. noidea_77, The computer that I turn on first works. the keyboard works. mouse works. and speakers. but when I click to switch, nothing happens.

 

[dbhosttexas]

Is this the little 2 port job? And is it PS2? If so, double check your cables, then check them again!

 

[cooldowg]

Yes. It has 2 usb ports for keybard and mouse. then a VGA for monitor. NOT PS/2

 

[dbhosttexas]

Okay, so which usb goes where doesn't really matter...

 

[Windows7Novice]

Actually, I have a USB KVM switch and the USB ports where the mouse and keyboard plug in are labeled and must be connected to the correct devices. It looks like only the keyboard USB port watches for the SCROLL-LOCK, SCROLL-LOCK keystrokes. When the keyboard and mouse are reversed, the mouse and keyboard will work on the current PC, but the KVM will not switch to the other PC.

 

[juiceclone]

I have discovered that even though a usb keyboard or mouse WILL work correctly when connected to the comp directly, they may not work or will delay or stop the boot process when running thru a KVM switch. It seems necessary to use only "generic/plain" keyboard and mouse to stop the boot hang problem. My Microsoft wireless mouse was the total cause of this problem when used thru an electronic KVM and then thru another KVM with all mechanical switches. A "lighted" keyboard and another with the "special" keys that take you to your home page..etc, also gave some trouble! Seems counter-intuitive, but try different mouse and/or keyboard into the KVM and see if that does it. :>)

 

[prokvm]

I have discovered that even though a usb keyboard or mouse WILL work correctly when connected to the comp directly, they may not work or will delay or stop the boot process when running thru a KVM switch. It seems necessary to use only "generic/plain" keyboard and mouse to stop the boot hang problem. My Microsoft wireless mouse was the total cause of this problem when used thru an electronic KVM and then thru another KVM with all mechanical switches. A "lighted" keyboard and another with the "special" keys that take you to your home page..etc, also gave some trouble! Seems counter-intuitive, but try different mouse and/or keyboard into the KVM and see if that does it. :>)

 

[prokvm]

There are three kinds of KVM switches in the market regarding to USB KVM switches (because most of users are not using PS/2 keyboard or PS/2 mouse now, so we are not including PS/2 KVM switches now).

1. USB Hub based KVM switch
2. USB emulation KVM switch
3. USB DDM KVM switch (Dynamic Device Mapping).

Type #1 Hub based switches work just like you physically plug in the keyboard and mouse "every time" you select to different connected systems. It will work but it caused a long latency while switching.
Type #2 Emulation based switches ( most of KVM switches with hot-key selection are emulated USB kvm switches). You only can plug in the keyboard to the keyboard USB port in order to have the hot-key command works. It most likely only support very limited number of keyboard and mouse models, because the switch ONLY EMULATE some types of keyboard and mouse no matter what kind of keyboard and mouse you actuary plug in to the KVM switch.

With new types of wireless keyboard/mouse and new OSs ( such as Windows 7/8 or Windows 10), you had better looks for DDM based KVM switches which can cover more than 90% of keyboard, mouse or even touch screen monitor (all USB HID devices) to work with the KVM switches. Please google "DDM KVM switches". You will find a lots reviews and commands of DDM KVM switches.

 

[ColinD]

Just had exactly the same problem, which was how I found this forum entry. I have an older kind of KVM switch, using PS2 connections. My problem was, sometimes I'd be hitting 'scroll lock' half a dozen times and more, before the screen changed to show the other PC. Often it just wouldn't. Just on the off-chance, I tried another keyboard, one with the 'scroll lock' key on the top row of the middle block, to the right of the qwerty. It works perfectly. The one I'd been using had the 'scroll lock' on the very top row, where this replacement, working keyboard's 'Wake, sleep, power' keys are. Fantastic.
So my suggestion is: try another keyboard
Simples.