Category Archives: Technology

My blog posts related to technology, technical things and, in particular, computers and computer software.

How to rename bluetooth device in Windows 10

When my wireless QC30 headset connects to a device, it reads out “connected to [device-name]”. This is handy, but when for example connecting to my work laptop, which has a rather long cryptic alphanumeric name, it gets annoying instead. And since it’s a work laptop, I can’t just change the name of the device either, and frankly, I don’t want to have to do that either. I just want my device to have a different name specific to bluetooth. Turns out, you can actually do that:

  1. Run devmgmt.msc
  2. Find your bluetooth adapter under Device Manager / Bluetooth
    E.g. mine is called Intel(R) Wireless Bluetooth(R)
  3. Right-click and choose Properties
  4. Go to the Advanced tab
  5. Change Name
  6. Hit OK

And it’s done. 👍

Source: comment @

Excel time calculation and formatting

It’s actually really simple, but for some reason I just keep having to look up some of these… so… finally… note to self…

Calculations =X+Y
12:45 - 9:55 = 2:50
Time to decimal =X*24 2:50 * 24 = 2.83
Decimal to time =X/24 2,83 / 24 = 2:50
Days, hours, minutes d h:mm 11 19:20
Total hours and minutes [h]:mm 283:20
Total minutes [m] 17000

Regarding the formatting, without the brackets, it formats as regular time (total hours % 24). So, for example, 2 hours and 50 minutes multiplied by 100; with a regular time format (h:mm) it displays as 19:20; using brackets ([h]:mm) you get the correct 283:20, which is 11 days 19 hours and 20 minutes (hence the 19:20 from h:mm).

Excel screenshot

How to add certificates to the Windows certificate store

There’s a command-line tool called certutil one can use to add (among other things) certificates to the certificate store in windows.

Some examples:

REM Add pfx-file to Personal
certutil -ent -p pfxpassword -importpfx my some.pfx

REM Add pfx-file to Trusted Root Certification Authorities
certutil -ent -p pfxpassword -importpfx root some.pfx

REM Add cer-file to Trusted Root Certification Authorities
certutil -ent -addstore root some.cer