The wingpanel disappears after few seconds of starting up. I have tried many methods, trying to remove indicator-synapse and also reseting settings to default.
When I typed wingpanel in terminal it showed the following results -
[INFO 19:31:25.879082] Application.vala:155: System Panel version: 2.0.1
[INFO 19:31:25.879140] Application.vala:157: Kernel version: 4.4.0-47-generic
[FATAL 19:31:26.006260] wingpanel_widgets_overlay_icon_set_main_icon_name: assertion 'self != NULL' failed
[FATAL 19:31:26.007278] wingpanel_widgets_overlay_icon_set_main_icon_name: assertion 'self != NULL' failed
[FATAL 19:31:26.190710] [GLib-GIO] g_file_get_child: assertion 'G_IS_FILE (file)' failed
[FATAL 19:31:26.190785] [GLib-GIO] g_file_query_exists: assertion 'G_IS_FILE(file)' failed
[FATAL 19:31:26.190994] [GLib-GIO] g_file_get_child: assertion 'G_IS_FILE (file)' failed
[FATAL 19:31:26.191061] [GLib-GIO] g_file_query_exists: assertion 'G_IS_FILE(file)' failed
[FATAL 19:31:26.191135] gee_abstract_collection_get_size: assertion 'self != NULL' failed
[WARNING 19:31:26.191205] Theme.vala:508: Currently selected gtk+ theme 'elementary' does not provide a dock theme, fallback to the built-in defaults!
[FATAL 19:31:26.366372] [GLib] g_hash_table_get_keys: assertion 'hash_table != NULL' failed
[14:01:26.677358 Warning] [DesktopFileInfo] Unable to get exec for Other
[14:01:26.688649 Warning] [DesktopFileInfo] Unable to create AppInfo
** (process:3971): CRITICAL **: string_contains: assertion 'self != NULL' failed
** (process:3971): CRITICAL **: string_contains: assertion 'self != NULL' failed
[14:01:27.048320 Info] Tweaks.vala:307: Activating Tweak plug
[14:01:27.055878 Warning] GtkSettings.vala:48: Error loading GTK+ Keyfile settings.ini: No such file or directory
[14:01:27.055925 Warning] GtkSettings.vala:69: Error getting GTK+ int setting: Key file does not have group 'Settings'
[ERROR 19:31:27.175130] [GLib-GIO] Settings schema 'org.pantheon.terminal.settings' does not contain a key named 'opacity'
Trace/breakpoint trap (core dumped)