Mail activities stuck on Loading… in Windows project

[Venkadesh]

Hello UiPath Community,

I am facing an issue with Mail activities in a Windows project.

Problem

Activities like:

• Get Outlook Desktop Mail Messages
• Send SMTP Email

remain stuck on “Loading…” and never render the properties.

At the same time, I see multiple NU1202 compatibility errors in the Output panel.

I am using community version is 2026.0.182 STS

[loginerror (Maciej Kuźmicz)]

Hi @Venkadesh

Could you please add a screenshot of the activity packages that you have installed in this project?

[Venkadesh]

Hi @loginerror

Please check the screenshot attached

[vhvinodsai (Vinod harapanahalli)]

Hi @Venkadesh

Could you please check the SMTP properties values

[Venkadesh]

I am not able to see properities. Please refer the above screenshot @vhvinodsai

[vhvinodsai (Vinod harapanahalli)]

Hi @ashokkarale or @Anil_G

Could you please share your insights here

[ashokkarale]

@Venkadesh

Is it happening with new project as well?

Try deleting the project.json and reopen the project. Let the studio rebuild the project.json as per the requirement.

[Venkadesh]

Still getting same loading @ashokkarale

[ashokkarale]

@Venkadesh

Downgrade all the package versions by 1-2 versions and try.

Looks like you have incompatible package versions in your project. Look at first and last error lines.

Have you tried a new project? What’s the result?

[Gokul_Jayakumar (Gokul Jai)]

Hi @Venkadesh
It looks like you might be using .NET 8.0 version, and I think Mail activity is not supported for that yet. Could you please try with .NET 6? If possible, can you open the project.json and share the targetFramework?

Or else Try with Older Version 1.24.16

[Venkadesh]

Try with Older Version 1.24.16 - I have tried but still its loading @Gokul_Jayakumar

This is targetframwork

[Venkadesh]

@Gokul_Jayakumar

.NET 8.0 versi

Still I am getting the same issue. I have downgrade the package version.
I think its the issue is UiPath community version @ashokkarale

[ashokkarale]

@Venkadesh

It’s not the Studio issue. I tried recreating the issue but it’s working fine for me. I used Community Studio 2026.0.182 STS

Here is sample code, try to open it from your studio.

TestProcess.zip (112.3 KB)

[Venkadesh]

I am opening this fille but i see still loading issue

[Venkadesh]

@ashokkarale

[ashokkarale]

@Venkadesh

Ok so it’s clearly your network or system admin blocked the package feed url’s. If you are using personal machine, then delete the nuget cache and retry opening the code.

C:\Users\yourusername\.nuget\packages

[Venkadesh]

This is my company laptop @ashokkarale

[ashokkarale]

Got it @Venkadesh so it’s network firewall restriction mostly companies do apply.
Get these package feeds whitelisted from your IT team so the packages could be downloaded by Studio.

[Gokul_Jayakumar (Gokul Jai)]

@Venkadesh
Try below steps

1. Close the UiPath Studio
2. Navigate to the below folder ib your machine.

C:\Users\<UserName>\.nuget\packages

3. delete the folders relevant to the activities like below
microsoft.graph
google.apis.*
system.security.cryptography.cng
xamarin.*
mono.*
OrElse You can delete the all Folders (its like clearing the cache, UiPath studio must be closed before deleting it)

4. Restart the UiPath, it will automatically reinstall the Required packages.

[Venkadesh]

My system user is corrupted. So that only I got the loading issue. Now i am reset the PC and its working fine me @ashokkarale @loginerror @vhvinodsai @Gokul_Jayakumar