What is CSISYN~1.EXE?

CSISYN~1.EXE is part of Microsoft Office 2013 and developed by Microsoft Corporation according to the CSISYN~1.EXE version information.

CSISYN~1.EXE's description is "Microsoft Office Document Cache Sync Client Interface"

CSISYN~1.EXE is digitally signed by Microsoft Corporation.

CSISYN~1.EXE is usually located in the 'C:\PROGRA~1\COMMON~1\MICROS~1\OFFICE15\' folder.

None of the anti-virus scanners at VirusTotal reports anything malicious about CSISYN~1.EXE.

If you have additional information about the file, please share it with the FreeFixer users by posting a comment at the bottom of this page.

Vendor and version information [?]

The following is the available information on CSISYN~1.EXE:

Product nameMicrosoft Office 2013
Company nameMicrosoft Corporation
File descriptionMicrosoft Office Document Cache Sync Client Interface
Internal nameCsi Sync Client Interface Dll
Original filenameCsiSyncClient
Product version15.0.4420.1017
File version15.0.4420.1017

Here's a screenshot of the file properties when displayed by Windows Explorer:

Product nameMicrosoft Office 2013
Company nameMicrosoft Corporation
File descriptionMicrosoft Office Document Cache Sync..
Internal nameCsi Sync Client Interface Dll
Original filenameCsiSyncClient
Product version15.0.4420.1017
File version15.0.4420.1017

Digital signatures [?]

CSISYN~1.EXE has a valid digital signature.

Signer nameMicrosoft Corporation
Certificate issuer nameMicrosoft Code Signing PCA
Certificate serial number3300000088590e3c511fe26a67000100000088

VirusTotal report

None of the 47 anti-virus programs at VirusTotal detected the CSISYN~1.EXE file.

None of the 47 anti-virus programs detected the CSISYN~1.EXE file.

Hashes [?]


Error Messages

These are some of the error messages that can appear related to csisyn~1.exe:

csisyn~1.exe has encountered a problem and needs to close. We are sorry for the inconvenience.

csisyn~1.exe - Application Error. The instruction at "0xXXXXXXXX" referenced memory at "0xXXXXXXXX". The memory could not be "read/written". Click on OK to terminate the program.

Microsoft Office Document Cache Sync Client Interface has stopped working.

End Program - csisyn~1.exe. This program is not responding.

csisyn~1.exe is not a valid Win32 application.

csisyn~1.exe - Application Error. The application failed to initialize properly (0xXXXXXXXX). Click OK to terminate the application.

What will you do with CSISYN~1.EXE?

To help other users, please let us know what you will do with CSISYN~1.EXE:

What did other users do?

The poll result listed below shows what users chose to do with CSISYN~1.EXE. 93% have voted for removal. Based on votes from 80 users.

User vote results: There were 74 votes to remove and 6 votes to keep

NOTE: Please do not use this poll as the only source of input to determine what you will do with CSISYN~1.EXE.

Malware or legitimate?

If you feel that you need more information to determine if your should keep this file or remove it, please read this guide.

Please select the option that best describe your thoughts on the information provided on this web page

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Please share with the other users what you think about this file. What does this file do? Is it legitimate or something that your computer is better without? Do you know how it was installed on your system? Did you install it yourself or did it come bundled with some other software? Is it running smoothly or do you get some error message? Any information that will help to document this file is welcome. Thank you for your contributions.

I'm reading all new comments so don't hesitate to post a question about the file. If I don't have the answer perhaps another user can help you.

Dane writes

0 thumbs

I have a new HP Elite notebook. CSISN 1.exe*32 starts multiplying how many times it is running until it completely takes up all processes and uses 100% CPU and doesn't really allow anything to run on the laptop or run extrememly slowly. If I restart the laptop they diappear and slowly overtime, 20 minutes it does the same thing again. What needs to happen to prevent this?

# 16 Jun 2014, 17:15

Roger Karlsson writes

0 thumbs

@Dane: Found a forum thread where a user suggests that the problem can be solved by uninstalling SkyDrive or OneDrive:


# 24 Jun 2014, 8:28

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