FileInfo
extension

BK1 File - What is a .bk1 file and how do I open it?

Learn about .BK1 files and view a list of programs that open them.

Languages

EN

Overview

What is a BK1 file? Backup file created by Autodesk products, including AutoCAD Mechanical, Mechanical Desktop, and AutoCAD Map; stores a .BAK file that has been renamed with the ".bk1" extension; renamed when the Autodesk program terminates unexpectedly.

More Information BAK files are automatically created when users save drawing files. Therefore, when a program crashes, Autodesk applications try to rename the BAK file to BK1 to prevent a corrupted drawing file from replacing the original backup. NOTE: If the BK1 extension is already in use, Autodesk programs use ".bk2" through ".bk9," as well as ".bka" through ".bkz" and ".baa" through ".bzz" until a unique extension is found.

Popularity2.6/5

14 votes

Quick AppOpen with
VerifiedVerified by FileInfo.com The FileInfo.com team has independently researched all file formats and software programs listed on this page. Our goal is 100% accuracy and we only publish information about file types that we have verified. If you would like to suggest any additions or updates to this page, please let us know .

Document Icon

Breadcrumbs

DeveloperCA
Popularity2.5 | 8 Votes

Previous / Next

‹ .BK!.BK2 ›

In-Depth

.BK1 File Extension

3 file types use the .bk1 file extension.

Autodesk Backup File

DeveloperAutodesk
Popularity
2.6  |  14 Votes
 

What is a BK1 file?

Backup file created by Autodesk products, including AutoCAD Mechanical, Mechanical Desktop, and AutoCAD Map; stores a .BAK file that has been renamed with the ".bk1" extension; renamed when the Autodesk program terminates unexpectedly.

More Information

BAK files are automatically created when users save drawing files. Therefore, when a program crashes, Autodesk applications try to rename the BAK file to BK1 to prevent a corrupted drawing file from replacing the original backup.

NOTE: If the BK1 extension is already in use, Autodesk programs use ".bk2" through ".bk9," as well as ".bka" through ".bkz" and ".baa" through ".bzz" until a unique extension is found.

Open over 400 file formats with File Viewer Plus . Free Download

Programs that open BK1 files

Sort

Pricing

Program Name

Platform

Reset

X

Windows

Autodesk AutoCAD 2025

Free Trial

Autodesk AutoCAD Mechanical 2023

Free Trial

Category: Backup Files

Updated: July 27, 2010

Windows Indexing Service File

DeveloperMicrosoft
Popularity
2.6  |  10 Votes
 

File created by Indexing Service, a component of Windows used to automatically index file system search information; contains information used for making fast file searches in Windows; typically seen with the name propstor.bk1 .

More Information

BK1 files are often located within the C:\​System Volume Information\​catalog.wci\​ directory. Other catalog index files in this directory may include .BK2 , .PS1 , .PS2 , .FID , .000 , and .HSH files.

NOTE: Windows may also create BK1 files on external drives, such as USB flash drives.

Programs that open or reference BK1 files

Sort

Pricing

Program Name

Platform

Reset

X

Windows

Microsoft Windows

Paid

Category: System Files

Updated: May 16, 2011

ERwin Backup File

DeveloperCA
Popularity
2.5  |  8 Votes
 

Backup file created by ERwin Data Modeler, a data modeling program; contains a backup of a .ER1 diagram file; created automatically by ERwin when the ER1 file is opened; used to recover a data model file if the original becomes corrupted.

More Information

BK1 files are used by older versions of ERwin Data Modeler.

Programs that open or reference BK1 files

Sort

Pricing

Program Name

Platform

Reset

X

Windows

CA ERwin Data Modeler

Category: Backup Files

Updated: April 28, 2010

FAQ

What is a BK1 file?↓
Backup file created by Autodesk products, including AutoCAD Mechanical, Mechanical Desktop, and AutoCAD Map; stores a .BAK file that has been renamed with the ".bk1" extension; renamed when the Autodesk program terminates unexpectedly.

Related