Hello Caye,
The biggest question is what exactly are you trying to email?
There are many different setups depending on the module, with the most common ones being covered in the Email Troubleshooting Guide here:
community.dynamics.com/.../dynamics-gp-email-troubleshooting-guide-1743830067
The two common ones would be Remittances and Sales Orders. For sales documents its important to note that we can only email the "Blank Paper" versions of the reports.
For Remittances I will just copy out what I have in the guide:
Send Documents in email check box is grayed out when trying to send a Remittance
Note: Common issues for PM EFT Remittances
Issue: User is attempting to email Remittances, but the checkbox is grayed out:
Cause: This issue has a few different causes, usually setup or 3rd party involvement
Solution: Try the following:
1. Check to see if the vendor is setup to allow for emailing:
a. Go to Purchasing >> Cards >> Vendor >> select a vendor >> E-mail.
b. In the Send Forms as Email section confirm that Vendor Remittance check box is checked.
3. If this is correct, check to see if Mekorma MICR is installed, if so make sure the Mekorma MICR System Options are set to have email enabled, or else the "Send Document in email' checkbox in the Remittance window will not be available to mark (or grayed out). To check this setting, go to Microsoft Dynamics GP | Tools | Setup | System | Mekorma MICR | System Options. Mark the checkbox for 'Enable Email Remittance' and click Save.
4. More information regarding issues with this process can be found here:
community.dynamics.com/.../quick-step-guide-to-e-mail-pm-eft-remittances-in-mdgp-2015-2016
Outside of these the rest of the time it comes down to odd setup issues like customers not setup with a Statement ID or not setup for emails.
Hopefully this gives you enough to go off of.
Thanks!