Email button in preview stopped working

[ZensoftBelgiumHZ]

The email-button on the preview stopped working. Office365 was installed as mailclient. This worked fine till yesterday.
Now when the e-mail button is used it gives an error that there is no default mailclient installed.

On other PC's (also with office365) everything still works fine. We've checked the registry and WIN.INI for MAPI=1.
The registry and WIN.INI are correct.

how can we solve this .

[IDEAL Software Support]

We don't know, what goes wrong. Obviously your system is badly configured. Follow the hint in the error message and check the settings for the default mail client. (PS: We do not provide support on how to administrate Windows.)

[ZensoftBelgiumHZ]

We don't know, what goes wrong. Obviously your system is badly configured. Follow the hint in the error message and check the settings for the default mail client. (PS: We do not provide support on how to administrate Windows.)

All other (non-microsoft) software, like Acrobat PDF, installed on that PC has no problem to find the default mailclient. So for us its obvious VPE has a problem to find the default mailclient.
What does VPE check in the registry to find the default mail client?

[IDEAL Software Support]

Maybe you have not read the documentation: VPE supports two mail APIs, Simple MAPI and Extended MAPI.

Simple MAPI is activated by default. If for example your mail client software did not install or register a Simple MAPI layer, then this will cause the problem.

[ZensoftBelgiumHZ]

Maybe you have not read the documentation: VPE supports two mail APIs, Simple MAPI and Extended MAPI.

Simple MAPI is activated by default. If for example your mail client software did not install or register a Simple MAPI layer, then this will cause the problem.

I've red the documentation. And did a test with extended mapi ON and OFF.
We'll ask our customer to reinstall office365.