19-08-24 10:42 AM
Hello, we are currently trying to upgrade Blue Prism from 7.1.1 to 7.3.1.
We encountered a problem with our SAP CRM web application. We have multiple objects to work with the application, but they are blocking each other. We get this exception when we are trying to use actions from a second or third object:
Internal : Failed to perform step 1 in Navigate Stage 'Attach' on page 'Attach' - The requested title is associated with another instance of Blue Prism
We don't have any problems with any other application (web or other). The only workaround we found so far was to put a detach stage at the end of each action, which is ridiculous.
Can someone please explain this exception or share tips how to properly configure the objects so that they don't block each other?
01-10-24 04:49 PM
Hi @swolonda, thanks for explaining that. You got me looking into this obsessively. It affects how I design automations to a significant extent. If Blue Prism really does have a way to make it so only one instance is created per object, I think I would love that. The thing is that I always set my objects to background mode for utilities, and I've experienced it being that separate instances are created depending on the level it is called from.
Would you mind importing the attached release into your environment? What I did was just create some simple logic. I did this using 6.10.1 and then imported into 7.3.1, and both show the same results for me.
The Blue Prism community isn't letting me put the code directly in here for some reason, so I uploaded it to GitHub here:
https://github.com/DaveTheRpaGuy/BluePrismInstanceTest/blob/main/6.10.1_Dave_Instance_Test_2024.10.01_1128ET.bprelease
If Blue Prism uses the same instance for Object A regardless of whether it is called from the process level or from Object B, then the two circled data items should have the same value at the end. Take a look at it and let me know if you have the same results. I feel like we may not be talking about exactly the same scenario, and I'm hoping this will shed some light.
I can't overstate how much I would love it if I can make each object have only one instance. 😃
02-10-24 06:03 PM
I think.... objects are loaded from the database into memory once per calling process or calling object. Loaded into memory on first use if memory serves. However every calling parent/object will load it's own copy. So... if a Process A calls Object X it will be created for use by that process, if Process A then calls Object Y which in turn calls Object X - then Object X will be loaded to be used by Object Y and in effect exist twice in that run time.
07-10-24 11:17 AM - edited 07-10-24 11:17 AM
I think I'm experiencing a similar issue here v7.2.1. I'm launching Zendesk in Edge using my Zendesk - BASIC VBO. If I then try and use an action from my Zendesk - Dashboards VBO, I receive "Failed to attach - Object reference not set to an instance of an object.", unless I call a detach first on the Zendesk - BASIC VBO, in which case subsequent objects will attach.
23-11-24 07:27 PM
@LukasVeverka @Dan.Lister I think I know what the issue was. I don't know how I overlooked this before, but the Release Notes of 7.2+ say that the Application Manager mode affects the functionality of multiple objects being attached at the same time to the same application. The problem here is that when you import a release into 64bit Blue Prism (7.3.1 for example), it will by default have it selected to keep it as 32bit external mode for the application manager mode. I "think" that if you simply go into your objects and change them to be Embedded Mode then your objects can be attached at the same time. If either of you try this and it fixes your issue, please let me know because I'm very interested in that. However, the notes below to indicate it is a very viable option to simply detach and attach.
Here is a direct quote from the 7.4 Release Notes in the section where it talks about changes as of 7.2:
--- Start Quote ---
External Application Manager modes cannot be used to attach multiple business objects to the same
application at the same time
Multiple objects can only attach to an application at the same time when they are run using Embedded
mode. If an external mode is used, objects must attach in sequence (that is, the first object must detach the application before attaching with subsequent objects). To resolve issues:
• Run the target application in the same bitness as Blue Prism Enterprise and retain Embedded mode and
concurrent attachment designs.
For browser automations, Embedded mode can be used even if there is a difference in bitness between
Blue Prism Enterprise and the browser.
Using Embedded mode will result in the loss of the application timeout functionality that is
available with external modes.
• If bitness cannot be matched, redesign the process using an external mode and sequential attaches and
detaches of each object.
--- End Quote ---