I've been having some issues with the electricity in my apartment (potentially 1950's built) going to my electronics. I have two laptops (one of which is my work laptop) and an iPhone. Laptops are plugged into a surge protector but I don't think it's doing much.

Some of the issues I've been having on both new laptops (about a year old each) simultaneously are:

  • Data corruption (Windows Explorer says file not found, "invalid parameter", freezes, shows windows with no text or in a foreign language.) Decompressing files sometimes results in errors.
  • New monitor (a few months old) shows green, red, or blue noise. Unplugging the HDMI cord and plugging it back in again usually gives me a mild shock but relieves the symptoms for a while.
  • Applications take a very long time to launch or open with strange ungoogleable errors ("Unknown error" or "Invalid memory access in protected area".) I've never seen these errors before.
  • Running sfc.exe /SCANNOW usually results in many errors that are fixed, but after running it again a few days later, it continues to fix issues.
  • Icons disappear from the taskbar.
  • Random freezes, WiFi stops working, graphics are corrupted.
  • Sometimes I receive a shock when touching one of my laptops, or my hand feels itchy.
  • Text on the first item in the app list on my iPhone is invisible sometimes.
  • USB port on my KVM switch is all of a sudden super flaky and I cannot use it anymore. I tried resetting the switch but I think it's fried.
  • USB SD card adapter stopped working in both laptops. SD card is ok (plugged it in directly.)
  • Wireless mouse and keyboard have a lot of interference.
  • I debugged many blue screen errors with windbg and it's either the graphics driver, or a system file (which I don't have debug symbols for.)

I strongly suspect it is an electrical issue as:

  • I've run two different virus scanners; no issues.
  • Changed the graphics driver to five or six different versions, installed many updates, no fix.
  • My outlet tester says "open ground" when I plugged it into each outlet. The issues occur much more often or even 100% of the time when I'm running an air conditioner, or there is a thunderstorm.
  • I never experienced these issues when the laptops are running off of battery power.
  • Lights in my apartment dim or get bright randomly. Sometimes the power goes out but it's not very often.
  • One of the lights in the bathroom usually turns on while taking a shower.

I asked my landlord to send in an electrician. An electrician came in and said:

  • Something to the affect of "the wiring is old-fashioned."
  • The grounding looks ok.
  • Run the air conditioner on a separate circuit (i.e. in a certain outlet in my room.) However, after they left, this didn't fix the issue (I had the air conditioner completely unplugged and this issue still occurred.)
  • The final recommendation was that I should not use any outlets in my room for my electronics and I should charge them elsewhere. Unfortunately, since the battery in my laptop can only last so long and due to the secure nature of my work it would severely affect my productivity and so I can't work outside of my room.

A maintenance staff personnel said I could try an AVR UPS. I've ordered one but I've heard that a double-conversion UPS is better, but I don't know enough about electrical issues to know if this will fix it. The double-conversion UPSes are a bit on the expensive side ($1000) but if there's a high chance it'll fix my issues I'll get it.

I also have a roommate in a separate room and they have the same air conditioner as I do, but I don't know if it's connected to the same circuit.

What can I purchase/try/do to fix these issues?

  • Are you in US/Canada or someplace else? Jul 15, 2021 at 3:40
  • @manassehkatz-Moving2Codidact -- they are in Canada from their profile and the tag on the Q Jul 15, 2021 at 11:38
  • I don’t know about Canada but in the US buildings of that age had marginal grounding. I would suggest using a UPS uninterruptible power supply to power your sensitive equipment on the last factory build I was involved with we had a horrible time with grounding causing switching supplies that were interconnected to have communications problems the end result was a actual grounding problem due to all the harmonics generated from the switching supplies. We installed a large copper grid throughout the fab and that did the trick for most equipment but ion implanters required UPS the size of a semi
    – Ed Beal
    Jul 15, 2021 at 14:35
  • Not sure why the downvote no comment so reversed. Way two long ( tldr) I noticed dual conversion ups, a simple APC unit true ups would work fine for a couple hundred.
    – Ed Beal
    Jul 15, 2021 at 15:01
  • I just purchased and installed a AVR UPS and it says "building wiring fault." The manual says I should contact an electrician immediately and stop using the UPS. Given the electrician already gave it the ok, should I return the UPS?
    – alexyorke
    Jul 15, 2021 at 21:22

3 Answers 3


It sounds like one of your appliances has a ground fault. Appliances should not be biting you. What you need is a GFCI receptacle. If you have one in the bathroom, run a 3-prong extension cord from there to here. It will likely trip, but then, you can try different combinations of appliances plugged in and not plugged in until you find the one that is tripping.

Of course many people are too prideful to admit their appliances mighthave a ground fault. Don't be one of those people.

  • Hi, thanks for your answer. I just tried plugging in both laptops into a three-prong surge protector and plugged the surge protector into a GFCI outlet (in the kitchen) and it didn't trip. I opened both laptops and tried to do a few things with them but they seemed ok. Was the three minutes that I waited long enough or should I wait longer?
    – alexyorke
    Jul 15, 2021 at 21:34
  • 1
    You also need to also test every other thing associated with your computing environment. I.E. anything that connects via electrical cables of any kind to the laptop. The ground fault might be in a monitor, switch, hub, etc. Also, on any cable that has a metal shell, touch the metal shell of the cable to the metal sink or faucet. Jul 15, 2021 at 22:07
  • Hi, so I plugged in everything (monitor, switch, usb devices, usb microphone, two laptops, harddrive) in my surge protector strip and plugged that into a three-pronged extension cord which went to a GFCI outlet. I turned on everything and it didn't trip.
    – alexyorke
    Jul 16, 2021 at 0:06
  • Use it that way as long as you can. That incident where you got "bit" was supposed to have tripped the GFCI. Further, this will tell you whether the problem is with that particular circuit that you're plugged into. Jul 16, 2021 at 2:54
  • Thanks for the help so far. Would it be safe to run a 30 foot extension cord to a GFCI outlet that my UPS would plug into in my room, assuming that the cord has the right wire gauge? The UPS said the power draw was about 200W; the load was 1/4 of its capacity.
    – alexyorke
    Jul 16, 2021 at 3:17

The issue was resolved by adding two new outlet boxes that were correctly grounded according to my outlet tester. I haven't had any issues since.

Additional info (for other Googlers):

  • The embedded controller (EC) returned data when none was requested. The BIOS might be trying to access the EC without synchronizing with the operating system. This data will be ignored. No further action is necessary; however, you should check with your computer manufacturer for an upgraded BIOS. ACPI errors were occurring (five or so at a time.)
  • CBS.log errors from running sfc.exe: Warning: Overlap: Directory \??\C:\Program Files (x86)\ is owned twice or has its security set twice Original owner: Microsoft-Windows-shell32, version 10.0.19041.964, arch Host= amd64 Guest= x86, nonSxS, pkt
  • Audio latency was high and sometimes had crackles or pops.

You have a lot of different issues. Some are almost certainly related to the power supply in your building - shocks, interference, dimming lights. Many others may be related to power but could just be coincidence - Windows errors, icons disappearing, etc.

Wiring/power problems fall into several broad categories. I recommend you get a decent quality multimeter:

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Make sure it says CAT III 600V safety rating. Cheap junk is fine for testing 9V batteries, not for testing 120V receptacles.

There are a bunch of different problems. You will only be able to diagnose some of them with basic equipment, but that still may help get to the source of the problems.

Lost Neutral

This is unlikely (because everyone in the building would likely have problems) but is a BIG one, so worth looking for. With a lost neutral, 240V circuits will be fine but 120V circuits will vary dramatically, depending on what items are turned on at any particular time.

Check voltage in each receptacle. They should all be about the same - nominally 120V, but anywhere from 110V to 125V is perfectly normal. If you see some receptacles significantly lower (more than 5V) others, and especially if you see some less than 110V and some greater than 125V then you may have a lost neutral. Then try the same thing with major appliances (e.g., your air conditioner) turned on. If the voltages change in both directions, some up, some down, when the air conditioner or other major appliances are turned on and off then you likely have a lost neutral. This is either a major panel problem within the building or an electric utility problem outside the building. The bad news is that it can cause all kinds of strange things to happen. The good news is that it is usually relatively easy for the right people (utility company or electrician, depending on the location of the problem) to fix. It is not immediately obvious if you're not looking for it.

Insufficient Power

This is common in older buildings. It can be at the entire building or apartment level (and in fact wider than that - there are brownouts across entire countries at times) but it can also be at the individual circuit level.

Check voltage on your main "problem" receptacles (where you usually plug in your computers). Watch the voltage as you turn on/off the air conditioner and other devices. If you consistently get a drop when appliances are turned on and voltage recovers when they are turned off (e.g., 115V -> 105V and then back to 115V) then you just don't have enough power in the apartment. Most of the time this can be resolved by adding additional circuits. Unfortunately, adding additional circuits can be quite expensive, especially if it turns out the panel for the apartment is full. But showing actual voltage drops may help convince the landlord.

Lack of or Improper Grounding

"Open Ground", if properly diagnosed, simply means there is no ground wire connected. However, if the hot & neutral wires are connected properly and your devices don't need a separate ground (no 3rd pin) then it will not cause any direct problems. However, if your devices need a ground (the plugs have 3 pins) and you either don't have a grounded receptacle (you're using cheater adapters) or you have a grounded receptacle but ground is not connected properly (a true "Open Ground") then that needs to be fixed. However, from a pure life-safety perspective you can have a 3-wire receptacle with ground not connected but with an upstream GFCI providing protection and that is safe - but it will show "Open Ground" and won't dissipate ESD properly.

Other Wiring Problems

There are plenty of other possible wiring problems. For example, a "hot/neutral reverse" combined with "open ground" will simply show "open ground" on a standard tester but may lead to additional problems, including serious safety concerns. Checking for these types of problems gets a bit more complicated, and normally involves opening junction boxes to check wiring, which you should not do in a rented apartment for safety/liability reasons.

As far as solutions, assuming you can't convince the landlord to fix any problems, and assuming you can't/won't move out, a good quality UPS is actually a reasonable solution to a lot of problems. A double-conversion UPS essentially gives you your own independent power supply, which can solve plenty of problems including varying voltage, but they are not a cheap solution.

  • 1
    You'll also want a NRTL (UL, CSA, TUV, ETL) label to go with that CAT III 600V marking Jul 15, 2021 at 11:26
  • Which issues from the ones that you've listed would be able to be fixed by a double-conversion UPS only? I'm having issues with my AVR UPS, it says building wiring fault and tells me to stop using it immediately and call an electrician.
    – alexyorke
    Jul 15, 2021 at 21:35
  • If it's saying "building wiring fault", I really think you should get that resolved, or at least "understood" first. If the fault is "only" open ground, not such a big deal. But it may be more than that. In theory a double-conversion (i.e., always-on) UPS should take care of pretty much any voltage fluctuations. But it doesn't make a ground where there was none. Jul 15, 2021 at 21:41
  • 1
    With regards the potential broken or shoddy neutral problem, I would not disregard, because combined with neutral being used as ground, this could account for people being shocked by parts that should be grounded It can also cause a variety of dirty power problems including too much and too little voltage.
    – K H
    Jul 16, 2021 at 0:41

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