Error message: Decryption failed(null) when attempting to open an Excel document on iPad

This is not solved. I believe those who say it is are referring to a work around where you have to download the Microsoft Office app to your device(s). Only Apple is going to be able to solve this with a subsequent iOS update. Read my posts to find out how the work around works, its free and works well but its still a band-aid.

FYI.. ..  I just installed 14.2.1 on my phone and that did not fix it. The version notes did not mention this issue so I didn't have my hopes up too high. We'll have to keep waiting for a native Apple fix.

The reason this is working is because Apple did a fix. I was the first one to update here and report it mysteriously got fixed with no notification of an update. I tried resending to my email my password protected spreadsheet and while I was doing that it suddenly started working on the newly sent one and on the previous one. I didn’t install anything and don’t have excel on my iPhone.

Thanks AlbertoITALIA! That's what I thought. Since you have MS Office and Excel on your iPhone SE, what happens if you take your encrypted Excel file from your Mail app and save it to your "Files" app on your SE and then open it from there?

Instead of grabbing the Word app, grab the MS Office app which contains all three, Word, Excel and Powerpoint in one app. Still, even though you have this app on your device, you will not be able to open an encrypted file within Mail but can save the file in Apples File app and then open it from there. It will actually open in whatever MS Office file extension the file is.

As of the latest iOS 14.2.1 for the phone, its not fixed yet.

Thanks; I don't need Excel or PowerPoint access, so the Word App worked for me to open encrypted files. But I'll repeat to APPLE: this is inexcusable. You've built a cloud-based system where someone who has an important, password protected document needs to have access to the document on their "smart" phone. Spend a little less time on bells, whistles, and gender-neutral emoticons and a bit more time on things that actually have serious consequences in real life.

in fact, another iPhone 6s 2016, although updated to the latest version of iOS, has never lost the opening functionality of the encrypted EXCEL files. In fact, I used it to work for the last 6/7 days. I repeat, I found the problems in my new Iphone SE

I have Excel and Word on my iPhone but I’m not subscribed to Office 365. It started off as legacy software from Office 2011 on my Mac (pre subscription). Initially they were fully functional but when Microsoft support was withdrawn for that version it reverted to read only versions of the software at the next iteration on the App Store.

I have no MS Office software on my Apple phone but I’ver never had reading issues on encrypted files in the past ready from iCloud. BTW, I used MS Sync-sort to copy my encrypted files from my IBM PC to the iCloud and then read on my iPhone. I’ve also sent same encrypted file to phone as email attachment with identical issue,

Right, your complaint is the same as the rest of us, the ability to simply open a password protected MS Office file on our iPhone running 14.2 is gone till Apple fixes it.

Why not try downloading the free MS Office app from the App store, this is what worked for me. However, due to the issue Apple is having at the moment, you will still not be able to open your password protected file from within Apple Mail. However if you save that file to the Apple Files app, you will be able to open from there after installed MS Office.

You do not have to sign in to MS Office, just have it on your phone, its a stand along version, not 365. Try it and report back.

I figured out a temporary work-around until Apple fixes this. I converted my password protected Word document to a PDF, password protected the PDF, and then sent it to my iPhone. The decryption error does not occur with a PDF file.

For Word Documents and Excel Spreadsheet files download free Pages and Numbers app. Once you have those apps installed, long tap on the file and from Share Menu list select the app you want to file import to.

I’m still getting the message decryption failed (null) when I attempt to open an attachment, Word document, that requires a password. I have been able to open this document for years on both my iPhone and my iPad but now i can’t. I spoke with Apple today and they seem to think it’s somehow not their issue. Very frustrating!

It’s been working for me for a few days now. Absolutely nothing from Apple on this. I never saw an update notification.

But they for sure did something to fix it cause I did nothing myself to fix it.