As with most errors, there’s no single cause when it comes to “The server was unable to save the form at this time. Please try again.”
However, if the error is occurring for random/specific users and not everyone in your organization it’s most often just a permissions mismatch. If my solution below doesn’t solve your issue, scroll down further for other potential causes.
Make sure users granted library/list-specific permissions also have read access to the hosting site.
I see this error most often when a user is granted permissions to contribute to a SharePoint list or library, but doesn’t have any permissions at the site level. In other words, someone isn’t a member (edit) or visitor (read) of the site hosting a list or library to which they’ve been granted permissions.
The simplest fix is to create a new permissions group at the site level and give it read access to the site but edit or contribute permissions to the list/library. Or if you’re already putting users in a SharePoint permissions group to edit the specific list/library, just grant that same group read permissions at the site level.
For example, if you need to create a new group:
- Go to site settings > site permissions.
- Click Create Group.
- Name it, then be sure to select “Read” from the checkbox selection at the bottom.
- Add members (the individuals to whom you’d been granting access to the list/library who are getting the error).
- Go to the list or library settings > permissions for the list/library.
- Grant permissions > Add the new group and select contribute (or whichever level you’d been granting the individual users).
Or if you’re already putting users in a group for the list permissions, just go to site settings > site permissions and add that same group with read permissions.
Some users also report adding “use remote interfaces” to a read permission level when working with broken permissions to fix this issue. I haven’t had to do this, but my issues so far have only been general lists and don’t involve folders.
Check out these other resources if the above solution doesn’t solve your problem: