This problem occurs while using control RangeValidation
. And the answer I can use is following.
In webconfig
and search for:
1 2 3 4 5 |
<appSettings> <add key=" aspnet:UseTaskFriendlySynchronizationContext" value="true" /> <add key="ValidationSettings:UnobtrusiveValidationMode" value="WebForms" /> </appSettings> |
Delete <add key="ValidationSettings:UnobtrusiveValidationMode" value="WebForms" />
If there are no words above, adding <add key="ValidationSettings:UnobtrusiveValidationMode" value="None" />
in ‘appSettings
At last, fresh your page.