C4R – So You’re Missing Many Elements? (Part 1)

If you’ve been working on C4R for even just a little while, you have probably seen the dreaded ‘too many missing elements’ error.

When you’re opening a Revit model, there could be more elements in the central model than there is in your local model. Usually Revit will synchronise the changes with your local and the endless grind of office life moves on. Sometimes though, things just don’t work out and you’re presented with this

Luckily, there are solutions to get your files working again.

Step 1 – Clearing the Local Cache

First, we need to clear the C4R local cache on your machine. You have two choices here, either blow away everything in the cache, or just try to clean out the file that you’re having issues with.

The Cache Location

The local cache is located in %LOCALAPPDATA%\Autodesk\Revit\Autodesk Revit 201x\CollaborationCache where Autodesk Revit 201x is the version of Revit you are using.

The files and folders in the local cache are coded with unique GUIDs.

The first folder is your local machine code

The second level of folders are the projects. The files within the folders are the models related to the project.

 

In addition to the collaboration cache, there is another folder named PacCache which is located in %LOCALAPPDATA%\Autodesk\Revit\PacCache

The PacCache is where all the delta file transfer information is cached for all the C4R models that you have worked on. The PacCache isn’t split into individual projects, or even individual versions of Revit. Everything is lumped in the same folder.

This is where you take the easy way, or the (not really very) hard way.

Method 1 – The easy way.
Just Kill Everything.

It’s listed first simply because it’s easiest. This should actually be the last method you try for clearing out your cache.

The easy way is to just wipe out everything in both the CollaborationCache and PacCache folders. With Revit closed, just browse to the folders in your favourite file explorer you can delete the contents of the PacCache folder and then move everything inside the CollaborationCache folder to another location. You can delete the contents of the CollaborationCache as well, however I highly recommend moving just in case you need to restore backups. That’s right! There are local backups of your C4R projects and they’re located in these folders.

Just keep in mind that when you do this, it means you need to cache all the files with your local machine from the cloud again, so it might take some time the next time you open up your models, especially if you have quite a number of projects and models hosted on the cloud.

Method 2 – Just The (not really very) hard way.
Removing a Single File.

The hard way is to remove just the single file giving you grief. It’s actually not very hard at all, you just have to poke around in the journal file to find the specific GUID for your file.

The journal file is located in %LOCALAPPDATA%\Autodesk\Revit\Autodesk Revit 201x\Journals if you have just experienced the error, then you will need the most recent journal file.

The easiest way to find the most recent file is to change your file sorting by date modified with the newest files at the top.

Open the journal in a text editor (Notepad or Notepad++) and search for the name of the model causing the problem.

Search for the name of your Revit file in the journal. This will give you the GUID for the project and file.

Once you have found the name of the model, you need to search for the GUID by copying and pasting it into the search box and move all the files and folders with that GUID from the local cache folders.

The files and folders will be located in both the CollaborationCache and the PacCache folders. You need to delete the PacCache folder, but for the CollaborationCache you should move the folder that has the same GUID of file that you’re having trouble with without the {curly braces} to another location. Again, you can delete everything but if you do you won’t be able to restore any backups after the files are deleted.

Method 3 – Definitely way harder than it needs to be.
Clearing out a single project.

Clearing the cache for an entire project is quite a bit more difficult due to the PacCache folder is not sorted into Revit versions or even into projects and you need to clear out the PacCache because otherwise you’re going to have a bad time.

If you really want to head down this path, the easiest way to find the project GUID in your journal file.

Get the complete local path to the project folder within your Collaboration cache folder. Move or delete the project from the CollaborationCache folder. Again the same warning applies if you choose to delete the contents of your CollaborationCache.

C:\Users\<user name>\AppData\Local\Autodesk\Revit\Autodesk Revit 201x\CollaborationCache\<your local machine code>\<project guid>

Open up Google Chrome (Edge and Internet Explorer will not work), copy the full folder location to your project and paste it into the address bar in Chrome prefixed with file://

What this does is it lists all the files from the CollaborationCache in your browser. Copy the GUID of each Revit file without the .rvt extension and search for those GUIDs in the PacCache folder.

Delete any results you find from the PacCache folder.

Step 2 – Re-populate your local cache

Method 1 – Just re-open from C4R

The first method is to simply open your file again from C4R. Revit will populate your local cache with brand new copies of the files that you’ve moved or deleted so you can start fresh.

From experience this works maybe 80% of the time.

Method 2 – ‘Borrow’ Someone Else’s File

Borrowing.. Stealing.. Fixing your local C4R cache. Call it what you will. This method only really works if someone else is also currently working on the model. What you’re trying to do here is get yourself the most recent working copy of the file so that you lose as little work as possible.

You need to find someone else that is working on the project without any missing element errors, find who has the most recent copy and take only RVT file only from their CollaborationCache, do not take anything from the PacCache.

From experience this works the other 18% of the time.

One thought on “C4R – So You’re Missing Many Elements? (Part 1)

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.