Hi ​@xixu 

Thank you for reaching out, and I understand how concerning it must be to suddenly lose access to a file you’ve been actively working on—especially one that contains three months of important design work.

Since you’ve confirmed that you’re able to open other Lucidchart files, you’ve already tried duplicating and importing the file, and this particular file was fully accessible just a few days ago, it sounds like this may be related to the file size or potential corruption during a recent autosave.

Here are a few steps we can try next:

1. Open the file in Incognito/Private Browsing mode to helps rule out any browser cache or extension conflicts.

2. Check Version History (if accessible). If the file opens partially, try going to File > Version History to revert to an earlier version that may still be available.

3. Clear browser cache and refresh the session. A full cache clear followed by a browser restart can sometimes resolve session-related access issues.

You can also check out these tips here: Troubleshooting: Lost documents or work – Lucid

It would also be helpful to provide the following information for support here: Submit a request – Lucid:

• The document name
• The document URL if you were able to locate it using a bookmark, share link, or browser history
• Any email address you may have used to sign up for a Lucid account

I hope this helps. 

since i am not able to open the file, i do not have  access to the version history . all the website gives me is this 
Message: Our servers experienced an error. We apologize for the inconvenience.
Flow ID: 4c60acaaa91d3187
Time: 2025-06-08T15:18:09.423Z

it is a 404 error !

i tried 3 different computer already, cognito as well. i am able to login and open other files. 

the support ticket has been going on for 4 days now.  here is the request number , where it contains all the information. 

here is document url

please help me to recover the previous version, if it is a file save corruption

i can not believe this happens. and the case has been dragging for 4+ days without resolution.  

Hi ​@xixu, thank you for posting in the Lucid Community and thank you for confirming the steps you’ve tried from ​@Ria S’s troubleshooting suggestions! I am sorry you’re still having trouble with this. 

In an effort to protect your privacy, I have removed your document URL and ticket link from your post. I can see that you have a private support ticket open for this, and it appears that our developers and support staff are taking a closer look at this issue. They will be best equipped to continue helping through the private support ticket.

Since this deals with personal account information, I am directing this back to our support team so they can continue to get you taken care of. The team works through tickets in the order they are received, and you can continue to expect a quick response to your email associated with your Lucid account. Please refer to that email for further correspondence.