strange error

hello
first sorry for my bad english cause this is not my first language.

So i try to explain:

Yesterday i made a backup of my sql base.Today when i’m connected to my site all thing goes right but when i’m trying to answer to a comment i’ve got this error.

play_name] => Reynald [nickname] => SmartiesKiller [rich_editing] => true [wp_capabilities] => Array ( [administrator] => 1 ) [wp_sfadmin] => Reynald [wp_autosave_draft_ids] => Array ( [-1180890621] => 230 [-1180890648] => 0 [-1180956783] => 231 [-1181045851] => 232 [-1181210849] => 233 [-1181215844] => 234 [-1181215913] => 235 [-1181242683] => 236 [-1181243174] => 237 [-1181243656] => 238 [-1181244031] => 239 [-1181244139] => 240 [-1181244207] => 241 [-1181244281] => 242 [-1181244362] => 243 [-1181244438] => 244 [-1181469887] => 247 [-1181473495] => 248 [-1181504289] => 249 [-1181570394] => 250 [-1181570536] => 251 [-1181571084] => 252 [-1181571954] => 253 [-1181747679] => 254 [-1181842978] => 255 [-1182098485] => 256 [-1182098645] => 257 [-1182107490] => 258 [-1182116464] => 259 [-1182256208] => 260 [-1182257072] => 261 [-1182377359] => 263 [-1182901813] => 272 [-1182980771] => 273 [-1183546694] => 274 [-1183652616] => 275 [-1183652757] => 276 [-1183652846] => 277 [-1183658974] => 278 [-1183659004] => 279 [-1183659030] => 280 [-1183850383] => 281 [-1184699841] => 282 [-1184701733] => 283 [-1184701881] => 284 [-1184702510] => 285 [-1184702823] => 286 [-1184704063] => 287 [-1185014517] => 288 [-1185014671] => 289 [-1186571812] => 292 [-1186571888] => 293 [-1187360902] => 294 [-1189258825] => 295 ) [first_name] => Reynald [wp_user_level] => 10 [user_level] => 10 [description] => Fan de paranormal depuis toutjours. [wp_sfposts] => 19 [wp_sflast] => 2007-09-06 20:48:13 [wp_sfavatar] => 1181810634.png [s2_subscribed] => -1 [user_firstname] => Reynald [user_description] => Fan de paranormal depuis toutjours. ) [ID] => 1 [id] => 1 [caps] => Array ( [administrator] => 1 ) [cap_key] => wp_capabilities [roles] => Array ( [0] => administrator ) [allcaps] => Array ( [switch_themes] => 1 [edit_themes] => 1 [activate_plugins] => 1 [edit_plugins] => 1 [edit_users] => 1 [edit_files] => 1 [manage_options] => 1 [moderate_comments] => 1 [manage_categories] => 1 [manage_links] => 1 [upload_files] => 1 [import] => 1 [unfiltered_html] => 1 [edit_posts] => 1 [edit_others_posts] => 1 [edit_published_posts] => 1 [publish_posts] => 1 [edit_pages] => 1 [read] => 1 [level_10] => 1 [level_9] => 1 [level_8] => 1 [level_7] => 1 [level_6] => 1 [level_5] => 1 [level_4] => 1 [level_3] => 1 [level_2] => 1 [level_1] => 1 [level_0] => 1 [edit_others_pages] => 1 [edit_published_pages] => 1 [publish_pages] => 1 [delete_pages] => 1 [delete_others_pages] => 1 [delete_published_pages] => 1 [delete_posts] => 1 [delete_others_posts] => 1 [delete_published_posts] => 1 [delete_private_posts] => 1 [edit_private_posts] => 1 [read_private_posts] => 1 [delete_private_pages] => 1 [edit_private_pages] => 1 [read_private_pages] => 1 [delete_users] => 1 [create_users] => 1 [exec_php] => 1 [manage_polls] => 1 [manage_database] => 1 [use myGallery] => 1 [myGallery Settings] => 1 [administrator] => 1 ) [user_login] => admin [user_pass] => d8ea363365c125fbeae837cec35df042 [user_nicename] => admin [user_email] => [email protected] [user_url] => https://www.leblogdeletrange.fr [user_registered] => 2007-06-03 16:16:45 [user_activation_key] => [user_status] => 0 [display_name] => Reynald [nickname] => SmartiesKiller [rich_editing] => true [wp_capabilities] => Array ( [administrator] => 1 ) [wp_sfadmin] => Reynald [wp_autosave_draft_ids] => Array ( [-1180890621] => 230 [-1180890648] => 0 [-1180956783] => 231 [-1181045851] => 232 [-1181210849] => 233 [-1181215844] => 234 [-1181215913] => 235 [-1181242683] => 236 [-1181243174] => 237 [-1181243656] => 238 [-1181244031] => 239 [-1181244139] => 240 [-1181244207] => 241 [-1181244281] => 242 [-1181244362] => 243 [-1181244438] => 244 [-1181469887] => 247 [-1181473495] => 248 [-1181504289] => 249 [-1181570394] => 250 [-1181570536] => 251 [-1181571084] => 252 [-1181571954] => 253 [-1181747679] => 254 [-1181842978] => 255 [-1182098485] => 256 [-1182098645] => 257 [-1182107490] => 258 [-1182116464] => 259 [-1182256208] => 260 [-1182257072] => 261 [-1182377359] => 263 [-1182901813] => 272 [-1182980771] => 273 [-1183546694] => 274 [-1183652616] => 275 [-1183652757] => 276 [-1183652846] => 277 [-1183658974] => 278 [-1183659004] => 279 [-1183659030] => 280 [-1183850383] => 281 [-1184699841] => 282 [-1184701733] => 283 [-1184701881] => 284 [-1184702510] => 285 [-1184702823] => 286 [-1184704063] => 287 [-1185014517] => 288 [-1185014671] => 289 [-1186571812] => 292 [-1186571888] => 293 [-1187360902] => 294 [-1189258825] => 295 ) [first_name] => Reynald [wp_user_level] => 10 [user_level] => 10 [description] => Fan de paranormal depuis toutjours. [wp_sfposts] => 19 [wp_sflast] => 2007-09-06 20:48:13 [wp_sfavatar] => 1181810634.png [s2_subscribed] => -1 [user_firstname] => Reynald [user_description] => Fan de paranormal depuis toutjours. ) Please enter the authentication code.

i don’t touch anything since 2 months and today it make this crasy error when i try to post a comment.In preview comment it doesn’t do this error but when i clik on post comment it make it.

Thanks for the people who help me.Thx