Hi @asad.ali,
We are also facing the same issue. The problem is occurring when we trying to add stamp to a pdf or searching text with regex in a Multi-Threaded Environment. Of course only one thread works on one document at a time.
This is a blocker issue because it happens frequently and after that the Aspose.PDF library is unusable. Please handle this with higher priority!
Aspose.PDF version 21.1
C# .NET Core 3.1
Both Windows and Linux
The exception when adding stamp to the file:
System.InvalidOperationException: Operations that change non-concurrent collections must have exclusive access. A concurrent update was performed on this collection and corrupted its state. The collection’s state is no longer correct.
at System.Collections.Generic.Dictionary2.FindEntry(TKey key) at System.Collections.Generic.Dictionary2.TryGetValue(TKey key, TValue& value)
at #=zIiLJFlmpyWhFpRxTGDlVztAGfOcG1AWYOy3lTk46rVsq.#=zrwvLEkc$zO7_(String #=zO7PsOj0=)
at #=zigVcVy0kF4TRalKjQfSZwXS4h8Wr4JnYLsXkplRI$2JCT29t5nz2w4NK1LAL.#=z54VLcBk$o1QG()
at #=zigVcVy0kF4TRalKjQfSZwXS4h8Wr4JnYLsXkplRI$2JCT29t5nz2w4NK1LAL…ctor(#=znhMAf8uoh7npBu1BPoaM4ZimrtzOv7oOQQWyYqNeqDdW #=zznIXQcA71ooA)
at #=zvtO6Ng$WpwYB54ImeHA3xdoP5zJNoKntSl8GYV8=.#=zhTHOwCHHwSK4(#=znhMAf8uoh7npBu1BPoaM4ZimrtzOv7oOQQWyYqNeqDdW #=zlWgbMEo=)
at #=zvtO6Ng$WpwYB54ImeHA3xVSey26Ckbx4XpDH5bVPr6RX.#=z7xb$16RfzLPb()
at #=zvtO6Ng$WpwYB54ImeHA3xVSey26Ckbx4XpDH5bVPr6RX.#=zT2pqpVj0ZGay(#=zw06o7FsGWGj$QTygIS92HGXWE$0lss9XhA== #=zgF5L3ps=, #=z9JcVDy$g3fGYmDEmsqczqw$JbXT2hI55RQ==& #=zdc41hreDk0_8, #=z_uXQUUTOD1x0nWp6D5Ny5KFe8WGycG2EobghGDl1gz7q #=z4Gp8a2g=)
at #=zrqioYeoeEV9SrAkxSuXwlYngn91riM1bulStTlo=.#=zT2pqpVj0ZGay(#=zw06o7FsGWGj$QTygIS92HGXWE$0lss9XhA== #=zgF5L3ps=, #=z9JcVDy$g3fGYmDEmsqczqw$JbXT2hI55RQ==& #=zdc41hreDk0_8, #=z_uXQUUTOD1x0nWp6D5Ny5KFe8WGycG2EobghGDl1gz7q #=z4Gp8a2g=)
at #=zvtO6Ng$WpwYB54ImeHA3xVSey26Ckbx4XpDH5bVPr6RX.#=zT2pqpVj0ZGay(String #=zXTKSquQ=, #=z9JcVDy$g3fGYmDEmsqczqw$JbXT2hI55RQ==& #=zdc41hreDk0_8, #=z_uXQUUTOD1x0nWp6D5Ny5KFe8WGycG2EobghGDl1gz7q #=z4Gp8a2g=)
at #=zN0rxLZ0nC$n7nts4RfcoB2QiU0_xGQ8Dgomva8bkNK2O9QPC7hXd7T0sxyLBJBE24Csr1NU=.#=z9xqK_pI=(String #=zaqRXLAk=, #=zELMwkqufAmt6AlqpGYl3UyQeWyQADEhHV6C6tVA= #=zrLDk0sU=, #=zLlnBg5ePulKGl4$kf$7ZvAlalQnsxJtAzLArMToIsD1taZyUiMJjJCk= #=z$e5VP3yCF54m, Boolean #=z54GjP7g=, Boolean #=zBxRmBak=, #=z9JcVDy$g3fGYmDEmsqczqw$JbXT2hI55RQ==& #=zgF5L3ps=, #=znhMAf8uoh7npBu1BPoaM4ZimrtzOv7oOQQWyYqNeqDdW& #=z707kD2z5Gi7r, String& #=zc$o7mZrJN$XG)
at #=zvhGFYF4WvYmsypCRm15eZtb3Dck0aWOFsTGXeJo1VDJWF49JqBBgbFM=.#=z0vgjBV4=(#=zn99Y5yCMyviydefVXZU_ltsRZz8_fZ_vo9XE5b$PNOCemzkkGs_jJQY2nm4pc984NF7VjJRIuACCFMq$Xw==[] #=zBb8thboLLydj3c_4xUr4RiXpaxl1, String #=zaqRXLAk=, #=zELMwkqufAmt6AlqpGYl3UyQeWyQADEhHV6C6tVA= #=zrLDk0sU=, #=zLlnBg5ePulKGl4$kf$7ZvAlalQnsxJtAzLArMToIsD1taZyUiMJjJCk= #=z$e5VP3yCF54m, Boolean #=z54GjP7g=, Boolean #=zBxRmBak=, #=z9JcVDy$g3fGYmDEmsqczqw$JbXT2hI55RQ==& #=zlMpSlT8=, #=znhMAf8uoh7npBu1BPoaM4ZimrtzOv7oOQQWyYqNeqDdW& #=z707kD2z5Gi7r, String& #=zc$o7mZrJN$XG)
at #=zvhGFYF4WvYmsypCRm15eZtb3Dck0aWOFsTGXeJo1VDJWF49JqBBgbFM=.#=zzbkF4BMkwC1v(#=zELMwkqufAmt6AlqpGYl3UyQeWyQADEhHV6C6tVA= #=zrLDk0sU=, Boolean #=z54GjP7g=, Boolean #=zBxRmBak=, #=znhMAf8uoh7npBu1BPoaM4ZimrtzOv7oOQQWyYqNeqDdW #=zp4w5aRHAf18V, #=zIEV6AkUK7JTf7_aGwcjjY20= #=ziNEN5rsxAvRZ, String #=zXPxI6wQ=, #=zLlnBg5ePulKGl4$kf$7ZvAlalQnsxJtAzLArMToIsD1taZyUiMJjJCk= #=z$e5VP3yCF54m, #=z9JcVDy$g3fGYmDEmsqczqw$JbXT2hI55RQ==& #=zgF5L3ps=, String& #=ztPjJKz5SVw_X)
at #=zmcmFK44ua_78K0uhsdt3OkhLWSEeFPvxYs1vg22MlBDx6yg7GCH2EFY=.#=zzFGHbFv5PHbH(#=zIEV6AkUK7JTf7_aGwcjjY20= #=zon_i9J0=, Boolean #=z54GjP7g=, Boolean #=zBxRmBak=, String #=zXPxI6wQ=, #=zLlnBg5ePulKGl4$kf$7ZvAlalQnsxJtAzLArMToIsD1taZyUiMJjJCk= #=z$e5VP3yCF54m, #=znhMAf8uoh7npBu1BPoaM4ZimrtzOv7oOQQWyYqNeqDdW #=zqfxVrCfAyX4R, Font #=zBSSrwtSQaicm, #=znhMAf8uoh7npBu1BPoaM4ZimrtzOv7oOQQWyYqNeqDdW& #=zIaqij_c=, String& #=zo8Z7EaAXyCRm, #=z9JcVDy$g3fGYmDEmsqczqw$JbXT2hI55RQ==& #=zNMPnz$4=)
at #=zmcmFK44ua_78K0uhsdt3OkhLWSEeFPvxYs1vg22MlBDx6yg7GCH2EFY=.#=zP7Tamsk4m6_p(#=zIEV6AkUK7JTf7_aGwcjjY20= #=zon_i9J0=, Boolean #=z54GjP7g=, Boolean #=zBxRmBak=, String #=zXPxI6wQ=, #=zLlnBg5ePulKGl4$kf$7ZvAlalQnsxJtAzLArMToIsD1taZyUiMJjJCk= #=z$e5VP3yCF54m, #=znhMAf8uoh7npBu1BPoaM4ZimrtzOv7oOQQWyYqNeqDdW #=zqfxVrCfAyX4R, Font #=zBSSrwtSQaicm, #=z9JcVDy$g3fGYmDEmsqczqw$JbXT2hI55RQ==& #=zgF5L3ps=)
at #=zmcmFK44ua_78K0uhsdt3OkhLWSEeFPvxYs1vg22MlBDx6yg7GCH2EFY=.#=zP7Tamsk4m6_p(#=zIEV6AkUK7JTf7_aGwcjjY20= #=zon_i9J0=, Boolean #=z54GjP7g=, Boolean #=zBxRmBak=, String #=zXPxI6wQ=, #=zLlnBg5ePulKGl4$kf$7ZvAlalQnsxJtAzLArMToIsD1taZyUiMJjJCk= #=z$e5VP3yCF54m, #=znhMAf8uoh7npBu1BPoaM4ZimrtzOv7oOQQWyYqNeqDdW #=zqfxVrCfAyX4R, Font #=zBSSrwtSQaicm)
at Aspose.Pdf.Text.TextState.set_Font(Font value)
at Aspose.Pdf.Text.TextState.#=zrrnRTv7wlZT4(TextState #=zthMif_o=, #=zYbFUZszIhVZv_LsvLkbzFDtNCcAb_GX1$OF3BenQv6CVjEXlvg== #=zmZsZExc=)
at Aspose.Pdf.Text.TextState.#=zTICjGXU=(#=zmcmFK44ua_78K0uhsdt3OkhLWSEeFPvxYs1vg22MlBDx6yg7GCH2EFY= #=z6AW15U20daV_)
at Aspose.Pdf.Text.TextSegment.#=zTICjGXU=(#=zmcmFK44ua_78K0uhsdt3OkhLWSEeFPvxYs1vg22MlBDx6yg7GCH2EFY= #=z6AW15U20daV_)
at Aspose.Pdf.Text.TextBuilder.#=zPvcMFss=(TextFragment #=z29FLDHa_Av0q, Int32 #=zdG$BXlM=, Boolean #=z41Jx5nVgak87)
at Aspose.Pdf.TextStamp.Put(Page page)
at Aspose.Pdf.Page.AddStamp(Stamp stamp)