I considered not writing this response, because it's sort of embarrassing and might mean that I'll get more questions about it and might even be asked to fix it, but here goes. ;-) This can happen when you import and export ZClasses (not ZClass-based products, but actual ZClasses). There is a subtle bug in the ZClass registry code that can cause instances to refer to an older class definition. It's a pretty obscure bug but its bitten me before. A workaround is to export all of your ZClass-based products as well as all the objects in your root folder and start with a fresh Data.fs, reimporting everything as necessary. I know, I know. But it will work. ;-) Jens Vagelpohl wrote:

there is something in the ZODB that has a reference to the old class. maybe some old instances. also, try packing the database and restarting after that.

jens

On Monday, May 27, 2002, at 03:58 , Luis Martin Arganaraz wrote:

...

Hello everybody. My problem: I made a product with ZClass technology. I don't know why every time that I start Zope, an old version of my product appear. The unique information that I could find is in the file "stupid_log_file.log". This is:

2002-05-27T14:01:46 PROBLEM(100) ZODB Could not import class 'MixGraphClass' from module '*Z70QZ0TZA5T3p/X/EFDKrA=='

Before this problem appear the product work fine, and if I re-import the newest version after a start, the product work fine too. So I don't have any idea of what is happening and how I could solve this situation. I didn' t find anything in the newest version that didn't be in the older version that suggest me a "code error".

Can someone give me any suggestion?

Thanks, Martin

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-- Chris McDonough Zope Corporation http://www.zope.org http://www.zope.com "Killing hundreds of birds with thousands of stones"

Presumably, this is the source of the problem I've been seeing where I can't view the 'Advanced' tab of any of my ZSQL methods. I get the following:

Error Type: SystemError Error Value: Failed to import class _ZClass_for_ZPhotoAlbum from module Products.Photo

Maybe...

Ouch. Sounds painful. You're saying each folder, method, script, etc. in the root folder would have to be exported separately?

Yes... - C