"Heartbroken" people have lost their possessions after a storage warehouse was destroyed by a blaze which spread from a next door business.
The fire engulfed a polystyrene factory at Twinwoods Business Park, Milton Ernest, Bedfordshire, on 1 November.
Customers of Storing.com were sent an email on Friday saying the fire had spread, "totally destroying our facility where your unit/s were kept".
The company said it was "totally devastated".
It apologised for not telling customers sooner, blaming the delay on its IT being affected.
"We very sorry this has happened to your storage, but this is beyond our control," the email said.
The Bedfordshire company added it would be in touch within seven days with more details of the insurance position.
The BBC has approached Storing.com for comment. It is not yet known how many people have been affected.
Customer George Kotsiofides, said of his possessions, "it's all gone".
"Letters, photos, stuff that I've collected over 30 plus years, an original ZX Spectrum, the one I had as a child, and a load of out-of-print stuff... there's stuff that you can't replace and it's heartbreaking," he said.
Gemma Lacey is working in the United States and put her possessions into storage before moving.
"It was basically the entire contents of my flat, everything I've had since I was about 16," she said.
"There were obviously things that were irreplaceable, I had letters from my grandma who passed away about ten years ago, I'm an avid record collector, I had every record I'd collected since I was 14.
"I've gone from having the whole contents of an apartment to having nothing to go back to and that isn't a very nice feeling."
More than 60 crews from four counties fought the blaze, which sent thick black smoke across the sky and caused nearby workers to flee the area.
Bedfordshire Fire and Rescue has said it is not thought the fire was started deliberately and investigations were continuing.