u/EvilEarthWorm

I have a ~10 year old IBM/Lenovo ThinkPad that I paid >$3000 to buy for very important business use. Since I have no intention of redoing setting up all the apps I have setup there, I have to fight to stop Windows Update from destroying it like it did to one of my other old PC.

The sneaky Windows Update service keeps re-enabling itself after repeated manual stop/disable. It and other stuff like MSFT Antimalware service detects the PC being idle and starts to use CPU (for bitcoin mining for MSFT who knows?) and the PC fan will start to spin (dusts / aged fan causing overheating is the main cause of old laptop dying). As a proof, as soon as I start using the PC the CPU usage goes back to 0% and fan stops.

I use a mouse wigger to trick them into thinking the PC is in use, but it only works sometimes.

But I found a really good way to stop all this I wanted to share. In my C drive there is a file that is exactly 1GB in size. I simply copy & paste this file repeatedly until the empty space in C drive drops below ~1GB. Now Windows Update have no space to download update and will stop using CPU and my PC is dead quiet with no fan running.

As soon as I need to install some app and need disk space, I simply remove some of these copied files and make just enough space.

Hopefully this trick helps!

Hello guys, how are you? I would like you to help me solve a problem.

I have a Windows Server on my server machine, and because of power outages it restarted unexpectedly. Now it is stuck on the startup screen with the spinning dots, and it stays like that.

Is there any solution to this problem, please?

I work at a small company as an IT technician. I am the only technician. Our IT department consists of me and my boss. This is my first professional IT job, but I also have a degree in Computer Science, so I am at least somewhat knowledgeable across a broad area of computer and tech domains. I've been working at this company for about 7 months now.

The other day I noticed that all of our support ticket responses were going to quarantine, so users were not able to see replies. I checked quarantined messages in EAC because I thought it was weird that no users were responding to any replies that I sent through tickets.

I informed my boss about this and he said he would take a look. Being curious, I inspected the headers of a quarantined email and found that DKIM wasn't aligned with our domain, so even though DKIM and SPF were passing, our anti spam/phishing rules were quarantining the emails, due to a DMARC misalignment issue. I know policies were tightened down recently in response to a bunch of phishing emails going to our users.

I didn't mention any of this to my boss, as I assumed he would find the issue and fix it. I was only looking out of curiosity and wanting to understand what the problem was. There has also been incidents in the past where I've tried to help but it has backfired.

I eventually noticed that there was a typo in our DNS records for the DKIM key records for the ticketing platform that we use. Our domain was duplicated in the hostname. So instead of dkim.ourdomain.com, it was dkim.ourdomain.com.ourdomain.com.

I brought this information to my boss a few days later, when I noticed that some emails were still being quarantined and that replies that were going through showed "unverified sender" inside of Outlook.

Long story short, he called me and was very direct about how I shouldn't be looking into that and that what I found in our DNS records didn't apply. Keep in mind I don't have access to our domain provider, I only used nslookup to query them. Emails were technically flowing again, but some support emails were still being quarantined and it looked like he created a bunch of rules within Exchange to force the support emails through.

He said that nslookup doesn't tell the full story, and that he wants DMARC to fail sometimes so that he can create rules in Exchange to allow certain mail through.

He kept asking me questions about SPF and DKIM and mentioned that he didn't know how much I actually understood, and that he didn't want to get too much into the weeds because he wasn't sure if I would understand.

I am not an expert on DKIM, SPF, DMARC, or mailflow in general. I did setup my own home lab with an M365 Business Premium trial so that I could break things and learn at home, and I also set up a free trial of our ticketing software so that I could reproduce and understand this issue better at home. That's mainly what gave me the confidence that I found the proper fix, because I was able to fix the support emails being quarantined in my lab by adding the correct records given by the ticketing system.

By the end he told me that the duplicate domain that I saw didn't matter, and that is how DNS is supposed to work. However, when I checked the record again about 15 minutes later, I saw that it had been fixed (it has a TTL of 5 minutes, so the cached record cleared pretty quickly). In addition to this, support emails are now coming through with DMARC passing, and our support email no longer shows up as an unverified sender.

The whole experience was fairly demoralizing. I was excited that I found the fix, and that it was just a simple typo in the DNS records, but my boss drilled into me about how I wasted my time and that I need to let him know before I go off exploring like that because he doesn't want me wasting my time.

I feel really bad about this now. Did I do something wrong by exploring this issue on my own? Is my understanding of DKIM and DMARC incorrect? I assumed that you always want DMARC to pass, and that you don't really have any control over whether it passes or fails outside of making sure your records are correct.

My understanding of SPF is that it passes when the sending IP has permission from your domain to send email on your behalf, and that DMARC passes via SPF when the return-path matches your domain. My understanding of DKIM is that a message can pass if signed, but DMARC will only pass if the signing domain matches the From field.

EDIT: I just want to thank everyone who bothered to read this post and add your input. It really helped me feel better about the experience and gave me confidence to keep doing what I'm doing. It really made my day :)