# Cannot open project / Error e0400b **URL:** \ **Category:** PIX4Dmapper\ **Created:** [March 26, 2021, 4:52am UTC](https://community.pix4d.com/t/cannot-open-project-error-e0400b/17318 "2021-03-26T04:52:02Z")\ **Posts on this page:** 1\ **Showing post:** 2
**Author:** ![Christina](https://sea2.discourse-cdn.com/pix4d/user_avatar/community.pix4d.com/christina/32/303_2.png) [@Christina](https://community.pix4d.com/u/Christina)\ **Post date:** [March 26, 2021, 9:10am UTC](https://community.pix4d.com/t/cannot-open-project-error-e0400b/17318/2 "2021-03-26T09:10:49Z")
I hope this helps: > **[Error e0400: "Cannot open project..." - PIX4Dmapper](https://support.pix4d.com/hc/en-us/articles/115001464603-Error-e0400-%22Cannot-open-project%22)** > > Error > When trying to open a project file (.p4d) using PIX4Dmapper, the project fails to load and one of the following messages is displayed: > e0400a. "Cannot open project... The project file does no... see also this community topic: > [@Error e0400b: Cannot open project. Invalid Format](https://community.pix4d.com/t/error-e0400b-cannot-open-project-invalid-format/8285): > > I created a project using images from 3 seperate folders: images/part1 images/part2 images/part3 I processed step 1 and then attempted to upload to the cloud. Because there are duplicate file names I received an error. I followed the advice in this post: [https://community.pix4d.com/t/6212/comments/360000269126](https://community.pix4d.com/t/6212/comments/360000269126) and was able to open and save the project. When I later attempted to open the project I received the “Error e0400b”. From my forum searches it appears this is often related to using … --- _[View the full topic](https://community.pix4d.com/t/cannot-open-project-error-e0400b/17318)._