About 6 months ago, after having no luck with the crackling I was getting with my old Delta 66 Sound card, and after consulting with this site, I bought a Focusrite, Scarelt 2i2 external sound device. While the sound seems to be fine, I am bothered by one irritating phenomenon. I have spent hours and months with their tech support thru Email. Though they are responsive, we can’t get the problem to resolve.
The problem is that when I turn on my system—computer and synths—the computer indicates on the right lower task bar that there is no sound card detected. This occurs every time I turn on the computer. I then have to remove the USB plug that connects the sound device to my computer, leave it out for 10 seconds, and then reattach it. The icon then always changes to show that it IS connected. The icon IS accurate, since I have tried going into Sonar with the icon showing 1 thing or the other. When the icon says that there is no sound card detected, Sonar says the same.
Any suggestions? I have downloaded many new drivers and taken and  sent tech support many screen shots with “Latency monitor,” and would rather spend my little “hobby time” making music rather than trying to figure this out. The latest is that I have been working on disabling CPU throttling, but that didn’t help—assuming I did it correctly.
Thanks.
LNovik
 
System: Sonar Producer 8.5, Focusrite 2-i2, M-Audio Midisport 4x4 MIDI interface, Intel i5 650 @ 3.2 gHz, 6.0GB RAM, 64 Bit OS. Mackie 14 channel mixer; various synths

You problem is probably not with the Scarlett but with Windows. It is not rare for Windows to forget a connected device when it restarts. Sometimes this can be because the device fails to power on from the USB current prior to the time Windows is looking for devices on the USB. If you have an external power supply for the device use it. I think that is not an option for the 2i2, however. You should make sure that Windows is not powering off the USB port. see 
http://www.techsupportalert.com/content/how-fix-annoying-windows-usb-problem.htm
 
If the worst that happens is that you have to unplug and plug in the device to force windows to recognize it, consider yourself lucky.

I've had a similar problem with my USB interface, connecting it to a powered USB hub (even though the manual says not to) has cleared up the issue for me.

Great suggestions. I was able to follow the first very clearly detailed message and link by slartabarfast. Unbelievably, the first time I did it, the sound card WAS recognized upon rebooting. However, when I tried it a second time, it was NOT recognized. I will continue to try this in the next few days and let you know. Certainly, this DOES SEEM to be the solution.
PansFolly had reccommend a powered USB hub. That would be easy enough, but I just want to make sure what I would get. I assume it's sort of like an extention cord for USB's, except ?with it's own AC supply. Thus, 1 cord on the USB hub would go into 1 of my existing USB ports on my computer. The sound card would plug into the new hub. AND--there would be, I assume from the term "powered," another cord going from the hub to a wall type AC voltage outlet. (I realize I could also attach it to an AC strip as well, but I want to keep it clear and simple for myself.
Thanks for both of your inputs.
LNovik
 

I did look up the "powered USB hub," and I'm pretty sure it's the same as what I'm describing in the note above. When, in  Device Manager, I look up the speed of my USB ports, it says something like "enhanced USB." I did see in one website that if it were a USB 3.0, it would say that, and not  just "enhanced." Thus, I think a 2.0 powered USB hub is what i'll buy in the next few days, unless I hear anything contradicting this.
 
And, to respond to startabarfast: as I said, I thought this solution seemed to be the perfect answer. However, as I continued several more times last nite to reboot my computer after DISABLING this item that your link talks about in Device Manager, the sound card continued to NOT be recognized. I even tried this in "high performance" mode as well as the regular "recommended" configuration.
LNovik

I had picked out my powered USB hub, but I was just waiting on a few things before I pulled the trigger. Specifically, the people from Focusrite said I should contact Dell directly and tell them how my computer is not responding. While I don't disagree, the fact is that I would think I'd have to pay close to $75 (my guess) to get support for a 3 year old computer which is out of the warranty period. 
However, an even more interesting development is the following. I have been finding in the past few days that when I first just power up my computer, without simultaneously turning on the other strips attached to my approx 5 hardware synths, the sound interface IS recognized right away. No unplugging and plugging! The reason I had never tried this before was that I had my computer connected to a separate power strip, so that when I would shut down the rest of my setup, I wouldn't have to wait for my computer to take the extra 30 seconds or so to finish powering off. However, my monitor was always connected to the power source of the rest of the instruments. Thus, I had no way to see what might happen if I just turned on the computer without turning on everything else.
IN the past week, I have connected the computer's monitor to the same power strip as the computer. I can thus now see that every time I turn on the computer (and monitor) without turning anything else on, the soundcard IS recognized. 
I mainly say all of this just to see if this gives anyone a hint as to why the sound card is NOT recognized when I turn both power sources both on at the same time. Of course, it's not just hardware synths that are attached to a common power strip, but some other units as well, such as some type of vocal effects box. There is probably another computer on that strip as well, which I use for other purposes sometimes. Hmmm.
Thanks for your time.
Larry Novik

I’ll cut to the chase: adding a powered USB Hub completely cured my problem Meaning that when I now turn on several power strips that power my computer and instruments, the Scarlett sound module box is now recognized. Prior to this, for the past 6 months, I would have to disconnect the USB cable from the computer for 10 seconds, and then reconnect. Nothing terrible, but an irritation.  I had found that just prior to buying the powered USB hub, that when I first turned on the computer and monitor alone, the sound card would be recognized after the computer went thru it’s 2 minute boot process. However, if I would turn on the power strip that supplied the other instruments any time before this boot process was complete, the card would NOT be recognized. Thus, getting the powered USB hub was the only thing in a long line of measures that made any difference. Thanks very much to     for suggesting this, PansFolly.
I should add the powered USB hub I bought is an Amazon Basics brand,  with 2 different types of USB outputs. One is for more powerful devices, as opposed to simple things like computer keyboards. I have connected my soundcard to the more powerful output port.
LNovik

I have a Scarlett 2i4 and never had this problem with my Win 7 system.  However, I have a problem in that upon startup, sometimes Windows fails to recognize my internal SATA drive which has all my documents (my C: drive is an SSD).  So Windows boots up, but I can't get to any of my documents.  I've just resorted to putting my PC into sleep instead of shutting it down, and it seems to hang on OK.

I'd be looking at updating the BIOS and chipset drivers myself.
Also see if there is a firmware upgrade for the hard drive.
Make sure you are on the latest windows updates.
If it persists after this, temporarily turn off power management features.

Yet another thread about why USB powered interfaces are to be avoided. 
USB was never originally intended to supply power and every system is going to supply it a little differently. USB 3.0 was designed with powering devices in mind, but an audio interface should always have the option of using an AC adapter.