- Developer: Microsoft
- Description: Mobile Device Remote API
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By landing on this page you are most probably trying to download the Rapi.dll DLL file to get rid of the error:
On this page, I have laid out the information you will need to know to understand what is causing this error as well as the versions of Rapi.dll which are sorted by age and type of operating system.
What is the Rapi.dll file?
The RAPI library contains information that the Windows operating system uses to communicate and sync with mobile devices.
Originally added to the operating system in 1996, the official name for the package is ActiveSync.
Programs that you have installed on your operating system may also need the DLL if they interact with mobile devices.
When running, the ActiveSync process can sync emails, contact and folders with mobile devices connected to your machine.
Why do I need this file?
You will need this file in the Systems/32 folder within your Windows operating system installation to synch up mobile devices and your computer.
Without the DLL on your system will find that you are unable to attach a portable device and exchange information between them.
Any programs that also use this functionality, such as Apple iTunes may also experience problems as they call this DLL into themselves.
DLLs are a popular method for software developers to add existing functionality into their core functions without having to write it from scratch.
What you can do as a quick fix is download a copy of the DLL further down this page and place it in your System32 folder.
This may just overwrite a corrupted copy of the DLL on your system and fix the issue, otherwise, you may have to roll your sleeves up and dive deeper.
Why is the Rapi.dll is missing error appearing?
A common cause of this error is that the company you have bought your PC from has forgotten to install the library.
On the other hand, if you have an older computer then it could be a sign of a more sinister issue in the form of a hardware or software fault.
A worst-case scenario is that you may have a virus lurking on your computer that is deleting important files and libraries to cause the user pain or even hold you to ransom.
The first and easiest solution to this issue is to re-install the Rapi.dll library from this page, then if unsuccessful try a new anti-virus program.
How do you fix the problem?
The simplest solution to fix the “Rapi.dll is missing” error and download the appropriate DLL file listed below.
After you have chosen the correct file and the download has finished you will need to put it in the target folder, as the warning message will let you know.
If you do not feel you are able to perform this task then you can download software that will try to automatically fix this for you by following these steps:
- Method 1: (DIY) download/install DLL yourself
- Method 2: (Auto) Have a program do it for you
- Method 3: (Semi-Auto) Use the system checker built-in admin tool to find a fix
- Method 4: (Anti-Virus) Install a new anti-virus and see if that can find and fix the problem
- Method 5: (Restore) Restore your system to a time before the problems began
Method 1: (DIY) download/install DLL yourself
Underneath this block of text are the versions of the Rapi.dll that we have found and cataloged, choose the right version for your system then download and install.
Rapi.dll, available versions:
|32/64 Bit (includes most recent)||Auto Fix||U.S. English||Download|
|32 Bit 22.214.171.12458||Mobile Device Remote API||U.S. English||Download|
|32 Bit 6.0.6000.16386||ActiveSync RAPI Backward Compatibility||U.S. English||Download|
|32 Bit 4.5.5096.0||ActiveSync RAPI Backward Compatibility||U.S. English||Download|
Which version of Rapi.dll do I choose?
Ideally, you will want to choose the most recent (highest version number) DLL file with the correct 32 or 64-bit label for your system.
Choosing a 64-bit version of the file will help ensure that your system can take advantage of the faster processing power available in your PC.
Where should I place the DLL once downloaded?
First, try placing the file into the folder where the program you are having problems with lives.
Usually, if you have an error telling you that this file is missing it will tell you where it is missing from.
What if I need to register the Rapi.dll file?
Once you have attempted the simplest solution of placing the DLL file into the target folder and found it hasn’t worked then you may have to register the change with Windows.
To do this you can save the DLL file to the C:WindowsSystem32 folder and then open a command prompt using admin rights, type “regsvr32 Rapi.dll” and run it.
Method 2: (Auto) Have a program do it for you
A program exists that will take the hard work out of fixing your missing Rapi.dll file problem called Auslogics.
The Auslogics suite of programs can keep your computer ticking by and ensure that the drivers and DLL files remain in working order.
Click "Download Solution" to get the PC tool that comes with Rapi.dll. The utility will automatically determine missing dlls and offer to install them automatically. Being an easy-to-use utility, it is a great alternative to manual installation, which has been recognized by many computer experts and computer magazines. Limitations: trial version offers an unlimited number of scans, backup, restore of your windows registry for FREE. Full version must be purchased.
It supports such operating systems as Windows 10, Windows 8 / 8.1, Windows 7 and Windows Vista (64/32 bit). File Size: 3.04 MB, Download time: < 1 min. on DSL/ADSL/Cable
Method 3: (Semi-Auto) Use the system checker built-in admin tool to find a fix
Those familiar with the Windows operating system will know of the sfc/scannow file integrity check for important files.
You can run this tool by doing the following:
- Start by launching the command line as an administrator (right-click to find the option) that you find in the search field using the keywords “command prompt”.
- In the newly launched window enter “sfc / scannow” without the quotes and hit the enter key to run the command.
- Now the program should launch and start working without any further input.
- You will know when the program has finished running and has been successful when a dialog appears saying “Windows Resource Protection found corrupt files and successfully repaired them.”.
Hopefully, the system checker will notice that the Rapi.dll file is missing and automatically fix it for you.
Method 4: (Anti-Virus) Install a new anti-virus and see if that can find and fix the problem
If you have been using your computer for a while and noticed that the Rapi.dll file has disappeared randomly while it has worked before then this can be a sign of malware.
A malicious piece of software could have deleted it in order to cause mayhem or maybe to hold you ransom for a payment to fix it.
The simplest fix would be for you to use the anti-virus built into the operating system called Windows Defender.
Method 5: (Restore) Restore your system to a time before the problems began
Like rolling back the clock and traveling back in time, the System Restore process built into various Windows versions allows you to roll your computer back to a time when it worked fully.
This is useful if you have problems such as a missing Rapi.dll file on your system and don’t know how it was lost.
You can attempt this yourself very easily by doing the following:
- Open the Start menu and launch the “Run” program by searching for it.
- With the “Run” program waiting for a command enter “rstrui” without the quotes and hit enter to open the system recovery tool.
- With the system recovery tool open you can choose a restore point to roll back to when you believe the computer was safe and worked fully.
Now when you fire your computer up again you will be able to find out if you went far back enough to when the Rapi.dll error did not appear.
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