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General discussion

Missing cryptoapi.dll File

Mar 29, 2017 2:52PM PDT

When I turn on my PC, I get an error message reading: "Program can't start because cryptoapi.dll is missing.

What is the best and safest way to restore this dll file?

Discussion is locked

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Re: cryptoapi.dll
Mar 29, 2017 3:07PM PDT

I don't have such a file on my Windows 7 system, so it's unlikely it belongs to Windows.

That means that the best way to restore it - if you don't have it on a backup - is to reinstall the program that it came with. Now it's up to you to check the list of startup programs (in msconfig>startup tab) or in sysinterals's autorun program to determine what program that is.

My guess, however: this file came with some malware and has been deleted by your antivirus. Then be glad it's gone. All you have to do then is remove the program that calls it from the list of programs that run at boot. The same tools as I mentioned above can be used for that.

A final question: what goes wrong now that unknown (to us) program can't run? If nothing goes wrong, it seems you don't need that file. Why restore it then?

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Missing cryptoapi.dll File
Mar 29, 2017 3:21PM PDT

Everything seems to be working o.k., so I will ignore it

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Are you using MyWinLocker or similar app?
Mar 29, 2017 3:13PM PDT

It doesn't appear to be in Windows 10 either so it's for some now missing app.

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Missing cryptoapi.dll File
Mar 29, 2017 3:24PM PDT

No I am not

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Was going to PS, add more
Mar 29, 2017 3:26PM PDT

But you have some startup item that is no more.

I use tools like HIJACKTHIS to get a report then find the item that is in the startup area. There are more ways to remove dead startup items than I can cover here. Use the one you like.

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Missing cryptoapi.dll File
Mar 29, 2017 4:39PM PDT

If the computer is working fine, why do I need to do this?

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To keep it clean and
Mar 29, 2017 4:47PM PDT

It could be malware, so for me, I'd clean it up.

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here's an article
Apr 5, 2017 10:35AM PDT