Germinating seeds puzzle

[SGD]

So far, I've grown 5 or 6 crops and I've never had a problem getting my seeds to germinate. My seeds are various strains of auto fems bought from a supplier recommended by this site and my usual process is to use the wet kitchen paper method and that has always worked perfectly.
This time I tried the same method twice with 4 seeds each time and nothing happened so I tried again just putting new seeds into the growing medium and again, nothing. The seeds are in my living room in a warm environment and are kept moist. I've read all the advice/instructions on this site and I've been following them to the letter.
Is it possible that the problem is with the seeds? I've had them for about a year and they are stored in a cupboard in my workshop which can get a bit cold in the winter. It seems odd that they have all suddenly died.

[Rwise]

Some time back I stored seeds in recycled medicine bottles, out of about 1000 seed I got 4 sprouts when I tossed them out. So they can go bad, how hot was the storage area? What were they in? I now keep my seeds in the fridge in zip locks.

[SGD]

They are in zip lock bags in a cupboard in my workshop but right now the temp is about 10C and in the summer it can be over 35C. They look fine, no signs of damp or mold.

[Bluey]

Keep them in the wet paper towel in total darkness longer...ive had seeds take a couple of weeks.
Cold storage of seeds will keep them longer for sure but must be dry and dark.
Paper towel method has always rocked for me...I use 21⁰C for germination.
If after a couple if weeks nothing then I'd consider tossing them.

[SGD]

OK, the latest attempt are in soil and have been there for 4 days with no sign of growth, I'll wait a bit longer. Previously, I could see the tap root appear after about 3 days.

[Rootsruler]

If you can dig them out you may want to give them a soak in water to soften the shell up?

I use a vertical germinator and have, so far, had 100% success.

[SGD]

OK, thanks. The current batch have been in damp soil for 4 days so I'll leave them for now.
Those vertical sprouts look very strong, I've usually got mine in the soil way before they are that size.

[Rootsruler]

I like to really establish a strong tap root as everything goes through it during the plants life cycle. When I plant them in soil and I start with a solo cup or similar pot, I'll place the bare tap in the cup centered in the middle and fill around with soil. If I plant them into 1 gallon cans I'll fill the pot and take a butter knife and stick it into the soil deep enough to accommodate the length of the tap. I wiggle the knife side to side to create an envelope and slide the tap into the hole being careful not to hurt any of the tertiary and secondary roots. Once they're in place I gently push the soil back and press on the media to firm it up and remove any air pockets. From there I bottom water them to make sure the entire media gets saturated.

I did a side by side test of vertically germinated seeds using my planting method versus normal seed in the ground. I vegged them for 4 weeks, removed them from their pots and shook out all the dirt from the root zone. VG plant had much more extensive tertiary roots running throughout the media along with a fatter tap root. Seed in soil plant had most of its tertiary roots running through the top half of the media with a few runners at the bottom. Tap was around 2/3 the size of the VG tap.

My guess is the longer tap root near the bottom was able to occupy the bottom half faster as the tap ran through the entire media top to bottom. The test was to see root development so I didn't replant and run them to harvest to see if there was a dry yield difference.

[Rootsruler]

The tap roots in the picture were in the germinator for 6 days.