diff --git a/public/locales/bg/validation.json b/public/locales/bg/validation.json
index d341eb735..26d075d9a 100644
--- a/public/locales/bg/validation.json
+++ b/public/locales/bg/validation.json
@@ -22,5 +22,6 @@
   "payment-reference": "Невалиден формат на кода за плащане",
   "eik-invalid": "Невалидно ЕИК",
   "help-us-improve": "Съгласявам се да се свържете с мен за подобрение на платформата.",
-  "positive-amount": "Сумата трябва да е положително число."
+  "positive-amount": "Сумата трябва да е положително число.",
+  "invalid-file": "Невалиден файл."
 }
diff --git a/public/locales/en/validation.json b/public/locales/en/validation.json
index 5225bf637..e3584afce 100644
--- a/public/locales/en/validation.json
+++ b/public/locales/en/validation.json
@@ -22,5 +22,6 @@
   "payment-reference": "Invalid payment code format",
   "eik-invalid": "Invalid EIK",
   "help-us-improve": "I agree to be contacted to help improve the platform.",
-  "positive-amount": "The amount must be a positive number."
+  "positive-amount": "The amount must be a positive number.",
+  "invalid-file": "Invalid file."
 }
diff --git a/src/components/admin/campaigns/grid/CreateForm.tsx b/src/components/admin/campaigns/grid/CreateForm.tsx
index 5432a7ae0..f0c87da97 100644
--- a/src/components/admin/campaigns/grid/CreateForm.tsx
+++ b/src/components/admin/campaigns/grid/CreateForm.tsx
@@ -25,7 +25,13 @@ const FormRichTextField = dynamic(() => import('components/common/form/FormRichT
   ssr: false,
 })
 
-import { ApiErrors, handleUniqueViolation, isAxiosError, matchValidator } from 'service/apiErrors'
+import {
+  ApiErrors,
+  handleFileUploadError,
+  handleUniqueViolation,
+  isAxiosError,
+  matchValidator,
+} from 'service/apiErrors'
 import { useCreateCampaign, useUploadCampaignFiles } from 'service/campaign'
 import {
   CampaignFileRole,
@@ -137,6 +143,7 @@ export default function CampaignForm({ initialValues = defaults }: CampaignFormP
     UploadCampaignFiles
   >({
     mutationFn: useUploadCampaignFiles(),
+    onError: (error) => handleFileUploadError(error, t),
   })
 
   const onSubmit = async (
diff --git a/src/components/admin/campaigns/grid/EditForm.tsx b/src/components/admin/campaigns/grid/EditForm.tsx
index 44a4772f1..1a4735cd0 100644
--- a/src/components/admin/campaigns/grid/EditForm.tsx
+++ b/src/components/admin/campaigns/grid/EditForm.tsx
@@ -23,7 +23,13 @@ const FormRichTextField = dynamic(() => import('components/common/form/FormRichT
   ssr: false,
 })
 
-import { ApiErrors, handleUniqueViolation, isAxiosError, matchValidator } from 'service/apiErrors'
+import {
+  ApiErrors,
+  handleFileUploadError,
+  handleUniqueViolation,
+  isAxiosError,
+  matchValidator,
+} from 'service/apiErrors'
 import {
   CampaignResponse,
   CampaignInput,
@@ -167,7 +173,7 @@ export default function EditForm({ campaign }: { campaign: AdminSingleCampaignRe
     UploadCampaignFiles
   >({
     mutationFn: useUploadCampaignFiles(),
-    onError: () => AlertStore.show(t('common:alerts.error'), 'error'),
+    onError: (error) => handleFileUploadError(error, t),
     onSuccess: () => {
       //invalidate query for getting new values
       queryClient.invalidateQueries([endpoints.campaign.viewCampaignById(campaign.id).url])
diff --git a/src/components/admin/donations/AddBankTransactionsFileForm.tsx b/src/components/admin/donations/AddBankTransactionsFileForm.tsx
index cac392ceb..2a6939f57 100644
--- a/src/components/admin/donations/AddBankTransactionsFileForm.tsx
+++ b/src/components/admin/donations/AddBankTransactionsFileForm.tsx
@@ -22,7 +22,7 @@ import FileUpload from 'components/common/file-upload/FileUpload'
 import GenericForm from 'components/common/form/GenericForm'
 import SubmitButton from 'components/common/form/SubmitButton'
 import FormTextField from 'components/common/form/FormTextField'
-import { ApiErrors, isAxiosError, matchValidator } from 'service/apiErrors'
+import { ApiErrors, handleFileUploadError, isAxiosError, matchValidator } from 'service/apiErrors'
 import {
   BankTransactionsFileType,
   FileType,
@@ -72,7 +72,7 @@ export default function BankTransactionsFileForm({
     UploadBankTransactionsFiles
   >({
     mutationFn: useUploadBankTransactionsFiles(),
-    onError: () => AlertStore.show(t('common:alerts.error'), 'error'),
+    onError: (error) => handleFileUploadError(error, t),
     onSuccess: () => AlertStore.show(t('common:alerts.message-sent'), 'success'),
   })
 
diff --git a/src/components/admin/irregularity/admin/grid/CreateForm.tsx b/src/components/admin/irregularity/admin/grid/CreateForm.tsx
index 0dc7c6e33..b8055301d 100644
--- a/src/components/admin/irregularity/admin/grid/CreateForm.tsx
+++ b/src/components/admin/irregularity/admin/grid/CreateForm.tsx
@@ -12,7 +12,7 @@ import { CampaignResponse } from 'gql/campaigns'
 
 import { Button, Grid } from '@mui/material'
 
-import { ApiErrors } from 'service/apiErrors'
+import { ApiErrors, handleFileUploadError } from 'service/apiErrors'
 import { createIrregularity, uploadIrregularityFiles } from 'service/irregularity'
 import { AlertStore } from 'stores/AlertStore'
 import { routes } from 'common/routes'
@@ -90,6 +90,7 @@ export default function CreateForm({ campaigns, person }: Props) {
     IrregularityInput
   >({
     mutationFn: createIrregularity,
+    onError: () => AlertStore.show(t('common:alerts.error'), 'error'),
   })
 
   const fileUploadMutation = useMutation<
@@ -98,6 +99,7 @@ export default function CreateForm({ campaigns, person }: Props) {
     UploadIrregularityFiles
   >({
     mutationFn: uploadIrregularityFiles(),
+    onError: (error) => handleFileUploadError(error, t),
   })
 
   const onSubmit = async (values: IrregularityInput) => {
@@ -122,7 +124,7 @@ export default function CreateForm({ campaigns, person }: Props) {
       AlertStore.show(t('common:alerts.message-sent'), 'success')
       router.push(routes.admin.irregularity.index)
     } catch (error) {
-      AlertStore.show(t('common:alerts.error'), 'error')
+      console.error(error)
     }
   }
 
diff --git a/src/components/admin/irregularity/admin/grid/EditForm.tsx b/src/components/admin/irregularity/admin/grid/EditForm.tsx
index ec6c0ad69..8903d681a 100644
--- a/src/components/admin/irregularity/admin/grid/EditForm.tsx
+++ b/src/components/admin/irregularity/admin/grid/EditForm.tsx
@@ -10,7 +10,7 @@ import { AxiosError, AxiosResponse } from 'axios'
 
 import { useMutation, useQueryClient } from '@tanstack/react-query'
 
-import { ApiErrors } from 'service/apiErrors'
+import { ApiErrors, handleFileUploadError } from 'service/apiErrors'
 import { endpoints } from 'service/apiEndpoints'
 import { editIrregularity, uploadIrregularityFiles } from 'service/irregularity'
 
@@ -98,6 +98,7 @@ export default function EditForm({ campaigns, irregularity, irregularityFiles }:
     IrregularityEditInput
   >({
     mutationFn: editIrregularity(irregularity.id),
+    onError: () => AlertStore.show(t('common:alerts.error'), 'error'),
   })
 
   const fileUploadMutation = useMutation<
@@ -106,6 +107,7 @@ export default function EditForm({ campaigns, irregularity, irregularityFiles }:
     UploadIrregularityFiles
   >({
     mutationFn: uploadIrregularityFiles(),
+    onError: (error) => handleFileUploadError(error, t),
   })
 
   const onSubmit = async (values: IrregularityEditInput) => {
@@ -132,7 +134,7 @@ export default function EditForm({ campaigns, irregularity, irregularityFiles }:
       queryClient.invalidateQueries([endpoints.irregularity.viewIrregularity(irregularity.id).url])
       router.push(routes.admin.irregularity.index)
     } catch (error) {
-      AlertStore.show(t('common:alerts.error'), 'error')
+      console.error(error)
     }
   }
 
diff --git a/src/components/client/campaign-application/steps/CampaignApplicationDetails.tsx b/src/components/client/campaign-application/steps/CampaignApplicationDetails.tsx
index b5454057c..10cd3dba6 100644
--- a/src/components/client/campaign-application/steps/CampaignApplicationDetails.tsx
+++ b/src/components/client/campaign-application/steps/CampaignApplicationDetails.tsx
@@ -66,7 +66,6 @@ export default function CampaignApplicationDetails({ files, setFiles }: Props) {
                 setFiles((prevFiles) => [...prevFiles, ...newFiles])
                 setFieldValue('applicationDetails.documents', newFiles)
               }}
-              accept="text/plain,application/json,application/pdf,image/png,image/jpeg,application/xml,text/xml,application/msword,application/vnd.ms-excel,application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"
             />
             {touched.applicationDetails?.documents && errors.applicationDetails?.documents && (
               <FormHelperText error>{t('steps.details.documents-hint')}</FormHelperText>
diff --git a/src/components/client/campaign-expenses/Form.tsx b/src/components/client/campaign-expenses/Form.tsx
index 289f7f750..3138dcf8e 100644
--- a/src/components/client/campaign-expenses/Form.tsx
+++ b/src/components/client/campaign-expenses/Form.tsx
@@ -21,7 +21,7 @@ import FormTextField from 'components/common/form/FormTextField'
 import { Checkbox } from '@mui/material'
 import { useCreateExpense, useEditExpense } from 'service/expense'
 
-import { ApiErrors, isAxiosError, matchValidator } from 'service/apiErrors'
+import { ApiErrors, handleFileUploadError, isAxiosError, matchValidator } from 'service/apiErrors'
 import { ExpenseInput, ExpenseResponse, ExpenseStatus, ExpenseType } from 'gql/expenses'
 import FileUpload from 'components/common/file-upload/FileUpload'
 
@@ -66,7 +66,7 @@ export default function Form() {
     UploadExpenseFile
   >({
     mutationFn: useUploadExpenseFiles(),
-    onError: () => AlertStore.show(t('common:alerts.error'), 'error'),
+    onError: (error) => handleFileUploadError(error, t),
   })
 
   let data: ExpenseResponse | undefined
diff --git a/src/components/client/campaign-news/secured/CreateForm.tsx b/src/components/client/campaign-news/secured/CreateForm.tsx
index 58ca10d8e..595436483 100644
--- a/src/components/client/campaign-news/secured/CreateForm.tsx
+++ b/src/components/client/campaign-news/secured/CreateForm.tsx
@@ -22,7 +22,13 @@ const FormRichTextField = dynamic(() => import('components/common/form/FormRichT
   ssr: false,
 })
 
-import { ApiErrors, handleUniqueViolation, isAxiosError, matchValidator } from 'service/apiErrors'
+import {
+  ApiErrors,
+  handleFileUploadError,
+  handleUniqueViolation,
+  isAxiosError,
+  matchValidator,
+} from 'service/apiErrors'
 import { useUploadCampaignNewsFiles } from 'service/campaign-news'
 import {
   CampaignFileRole,
@@ -111,6 +117,7 @@ export default function CreateForm({ campaignId = '', isAdmin = true }: Campaign
     UploadCampaignNewsFiles
   >({
     mutationFn: useUploadCampaignNewsFiles(),
+    onError: (error) => handleFileUploadError(error, t),
   })
 
   const onSubmit = async (
diff --git a/src/components/client/campaign-news/secured/EditForm.tsx b/src/components/client/campaign-news/secured/EditForm.tsx
index bed31df12..f23bdb421 100644
--- a/src/components/client/campaign-news/secured/EditForm.tsx
+++ b/src/components/client/campaign-news/secured/EditForm.tsx
@@ -27,7 +27,13 @@ const FormRichTextField = dynamic(() => import('components/common/form/FormRichT
   ssr: false,
 })
 
-import { ApiErrors, handleUniqueViolation, isAxiosError, matchValidator } from 'service/apiErrors'
+import {
+  ApiErrors,
+  handleFileUploadError,
+  handleUniqueViolation,
+  isAxiosError,
+  matchValidator,
+} from 'service/apiErrors'
 import { CampaignUploadImage } from 'gql/campaigns'
 import { ArticleStatus } from 'components/admin/campaign-news/helpers/article-status.enum'
 import ArticleStatusSelect from 'components/admin/campaign-news/ArticleStatusSelect'
@@ -123,7 +129,7 @@ export default function EditForm({ article, campaignId = '', isAdmin = true }: P
     UploadCampaignNewsFiles
   >({
     mutationFn: useUploadCampaignNewsFiles(),
-    onError: () => AlertStore.show(t('common:alerts.error'), 'error'),
+    onError: (error) => handleFileUploadError(error, t),
     onSuccess: () => {
       //invalidate query for getting new values
       queryClient.invalidateQueries([endpoints.campaignNews.viewNewsArticleById(article.id).url])
diff --git a/src/components/client/campaigns/CampaignForm.tsx b/src/components/client/campaigns/CampaignForm.tsx
index 6172f09a6..b962b5331 100644
--- a/src/components/client/campaigns/CampaignForm.tsx
+++ b/src/components/client/campaigns/CampaignForm.tsx
@@ -25,7 +25,7 @@ import {
   UploadCampaignFiles,
 } from 'components/common/campaign-file/roles'
 import AcceptTermsField from 'components/common/form/AcceptTermsField'
-import { ApiErrors, isAxiosError, matchValidator } from 'service/apiErrors'
+import { ApiErrors, handleFileUploadError, isAxiosError, matchValidator } from 'service/apiErrors'
 import { useCreateCampaign, useUploadCampaignFiles } from 'service/campaign'
 import {
   CampaignResponse,
@@ -114,6 +114,7 @@ export default function CampaignForm({ initialValues = defaults }: CampaignFormP
     UploadCampaignFiles
   >({
     mutationFn: useUploadCampaignFiles(),
+    onError: (error) => handleFileUploadError(error, t),
   })
 
   const onSubmit = async (
diff --git a/src/components/client/irregularity/helpers/IrregularityForm.tsx b/src/components/client/irregularity/helpers/IrregularityForm.tsx
index edb651695..87a37abea 100644
--- a/src/components/client/irregularity/helpers/IrregularityForm.tsx
+++ b/src/components/client/irregularity/helpers/IrregularityForm.tsx
@@ -11,7 +11,7 @@ import { FormikHelpers, FormikProps } from 'formik'
 
 import { StepLabel, Grid } from '@mui/material'
 
-import { ApiErrors, isAxiosError, matchValidator } from 'service/apiErrors'
+import { ApiErrors, handleFileUploadError, isAxiosError, matchValidator } from 'service/apiErrors'
 import { createIrregularity, uploadIrregularityFiles } from 'service/irregularity'
 
 import {
@@ -116,6 +116,7 @@ export default function IrregularityForm({ campaign, person }: Props) {
     UploadIrregularityFiles
   >({
     mutationFn: uploadIrregularityFiles(),
+    onError: (error) => handleFileUploadError(error, t),
   })
 
   const handleBack = () => {
diff --git a/src/components/common/file-upload/FileUpload.tsx b/src/components/common/file-upload/FileUpload.tsx
index 9078029c2..76e2e033c 100644
--- a/src/components/common/file-upload/FileUpload.tsx
+++ b/src/components/common/file-upload/FileUpload.tsx
@@ -5,21 +5,38 @@ const Input = styled('input')({
   display: 'none',
 })
 
+const mimeAllowlistStr = [
+  'text/plain',
+  'application/json',
+  'application/pdf',
+  'image/png',
+  'image/jpeg',
+  'application/xml',
+  'text/xml',
+  'application/msword',
+  'application/vnd.ms-excel',
+  'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
+].join(',')
+
 function FileUpload({
   onUpload,
   buttonLabel,
+  accept,
   ...rest
 }: {
   onUpload: (files: File[]) => void
   buttonLabel: string
-  accept?: string
+  accept?: string[]
 }) {
+  const acceptStr = accept ? accept.join(',') : mimeAllowlistStr
+
   return (
     <label htmlFor="contained-button-file">
       <Input
         id="contained-button-file"
         multiple
         type="file"
+        accept={acceptStr}
         onChange={(e) => onUpload([...(e.target.files as FileList)])}
         {...rest}
       />
diff --git a/src/service/apiErrors.ts b/src/service/apiErrors.ts
index d0f3f76d8..1f3da3434 100644
--- a/src/service/apiErrors.ts
+++ b/src/service/apiErrors.ts
@@ -1,5 +1,6 @@
-import Axios from 'axios'
+import Axios, { AxiosError, HttpStatusCode } from 'axios'
 import { TFunction } from 'i18next'
+import { AlertStore } from '../stores/AlertStore'
 
 const { isAxiosError } = Axios
 export { isAxiosError }
@@ -86,3 +87,16 @@ export const handleUniqueViolation = (
 
   return t('common:alerts.error')
 }
+
+export const handleFileUploadError = (
+  e: AxiosError<ApiErrors>,
+  t: TFunction<'translation', undefined>,
+) => {
+  const error = e.response
+
+  if (error?.status === HttpStatusCode.UnsupportedMediaType) {
+    return AlertStore.show(t('validation:invalid-file'), 'error')
+  }
+
+  AlertStore.show(t('common:alerts.error'), 'error')
+}